Fraport, the German-led consortium managing 14 regional airports in Greece, says Kos airport is operating as normal and “only with slight delays.”

The consortium said both take-off and landing runways and all airport buildings had been “extensively checked” for possible damage after the earthquake. Slight delays in scheduled local and international flights were expected to be ironed out during the course of the day, it said.

Professor Ethymios Lekkas, who heads Greece’s antiseismic protection organisation, has warned that Kos is likely to experience aftershocks “for up to two weeks.”

But, speaking to the Guardian, the geology professor insisted the activity would be good because the tremors would gradually reduce tectonic tension.

They will be well under five on the scale and won’t cause a problem. I am not worried. Buildings on the island have shown great resilience because they have been constructed to strict anti-seismic criteria.

The professor also clarified that the tidal wave caused by the quake and witnessed in Kos port was much smaller than originally reported. “It did not exceed 70cm and was very small,” he said.

According to the Associated Press, Turkey’s foreign ministry has now also confirmed that one of the two people who died on Kos was Turkish. That follows similar information emanating from Greek authorities.

The ministry said on Friday that a second Turkish national was in a serious condition and was being evacuated to Athens for treatment. It did not identify the victim, saying authorities were still trying to reach his or her family members.

Turkish authorities have sent a 250-person vessel from the Turkish resort of Bodrum to Kos to start evacuating some 200 Turkish tourists stranded on the island, the ministry also said. It said Greek authorities had granted the ship special permission to approach a pier at Kos where the port and customs building was damaged.

Greek authorities have now listed the five seriously injured people who were flown to Crete by emergency services earlier today as: two Swedes; one Norwegian; a Greek man and a Greek woman. One is reported to have suffered extensive leg injuries. All are thought to have been in the bar, whose roof collapsed, when the earthquake struck.

Between 2am and 4am, about 95 people were either admitted, or admitted themselves, to the local hospital on Kos. First aid was administered to about 85 more, who then left.

The quake, the second exceeding magnitude 6 to hit Greece’s coastal region in recent weeks, has produced more than 100 aftershocks, seismologists say. A second tremor measuring 5.1 struck 26 km south of Leros, after the initial earthquake measuring 6.5 hit Kos at 1.53am. Three further tremors measuring 4.6, 4.5 and 4.7 followed.

The quake is also believed to have caused a small tsunami in the port of Kos which subsequently suffered extensive damage.

The tidal wave was described as being about 70 cm high. A similar phenomenon occurred on Lesbos, in the port of Plomari, when an earthquake measuring 6.2 occurred in June. In sharp contrast to Kos, the tremor caused devastating damage with hundreds left homeless, prompting Pope Francis earlier this month to make a donation of €50,000 to boost relief efforts.

Tourists and residents in Bodrum spent the night outside on beach loungers or in cars. Boat captain Metin Kestaneci, 40, told the Dogan news agency that he was asleep on his vessel when the quake hit.

There was first a noise and then a roar. Before I could ask ‘what’s happening?’ my boat was dragged toward the shore. We found ourselves on the shore.

A London-based student, Georgie Jamieson, who was holidaying in Kos with her family, has described being caught up in the chaos. She told BBC Radio 4’s Today programme:

We’re all a bit shaken up. We had been having a lovely evening down in the hotel and got up to our room an hour before [the quake] struck.

We were literally dozing off when the first tremor struck. From then on it was a bit of a surreal nightmarish experience.

I was semi-conscious. At first I panicked and I was a bit fear-struck, but then slowly trying to process what was happening.

Everything was shaking really vigorously. I’ve never felt anything like it before. Almost as if the ground was going to cave in.

Jamieson said she went to check on her sisters and they were initially unsure whether it was safer to leave the hotel room or stay.

We ran to the door to check there was nothing outside that had been visibly damaged. When we saw that that was all clear, we were coming to terms with the fact that we were experiencing an earthquake and we grabbed our stuff and made a run away from the building.

The Greek armed forces have been put on alert with a 15-strong team from the country’s specialist search and rescue units, flying into Kos in the early hours. An 11-strong government delegation also arrived on the island a little after 4am. It includes the citizens protection minister, Nikos Toskas, and the transport minister, Christos Spirtzis.

The search and rescue units are expected to wade through debris – along with officials from the local fire services – lest there are other victims throughout the day.

“Slowly, slowly life is returning to normality,” the government spokesman Dimitris Tzanakopoulos told a local radio station, adding that, in contrast to a similar 6.2 earthquake that hit the island of Lesbos last month, the damage on Kos was limited.

Professor Ethymios Lekkas, who is Greece’s top geology professor and heads the anti-seismic protection organisation, says Kos should expect to be rattled by aftershocks for the foreseeable future.

“It was a big earthquake … aftershocks are happening and will happen,” he told the news portal newsit.gr, describing the tremors as “totally natural” and necessary.

For an earthquake of such magnitude, the damage had been very limited, he said:

With the exception of our two fellow human beings who died, the effects have been very small. We have had a very big earthquake … and only the port and two very big buildings have really been affected by it, which is very important and shows the level of construction.

Newly built hotel resorts had survived intact – testimony to their anti-seismic qualifications, he said.

Yiannis Glynou, who leads the technical chamber in the Dodecanese islands and is in Kos surveying the impact on buildings, told the country’s news agency:

The damage is limited to old stone buildings. New buildings on the island, including numerous hotel units, are showing almost none or no problems.

The quake struck at 1.30am local time in the early hours of Friday (22.30 GMT Thursday). By daylight, the damage in both the Greek and Turkish resorts affected is clearer to gauge.

Bodrum

Kos

Kos fire service rescue chief Stephanos Kolokouris has confirmed to Greek state television that the two people killed on the island were from Turkey and Sweden.

Both were men. They have not been named.

Kolokouris said both were tourists and died after a wall collapsed on to a bar in Kos old town close to the island’s main port. One of five people seriously injured was Greek, he said, but he did not give details of the other four.

Greek media are reporting that five people, three of whom have been “seriously injured”, have been flown by Chinook helicopter from Kos to Crete for treatment. Emergency services have rushed them to the island’s main University general hospital in Heraklion.

One of the injured is said to have suffered what are being described as “very severe injuries” to both legs.

Turkey’s disaster and emergency management presidency (AFAD) said it had observed a large number of aftershocks in Turkey and Greece following the 6.7 magnitude mainshock, several of them registering 4.0 magnitude or above.

Will Fell, a British tourist in Kos, told the Guardian:

It’s not fully stopped: there’s been lots of small aftershocks. Nothing as intense as the first mainshock that we had.

The United States Geological Survey (USGS), which monitors earthquakes, said the strong quake was very shallow – only 10km (6.2 miles) below the seabed – and located off the south-western coastal city of Marmaris in the Mugla province of Turkey.

The epicentre was just 10km south of the Turkish resort of Bodrum and 16km east/north-east of Kos, which has been the area worst hit.

The quake was also felt on the Greek island of Rhodes.

“We were very surprised. We were scared and we immediately went outside,” Teddy Dijoux, who was holidaying with his family at a Rhodes resort, told news agency AFP.

“That lasted a long time. I quickly gathered up my children to leave the hotel,” said holidaymaker Sylvie Jannot.

The 6.7 magnitude earthquake struck Turkey’s Aegean coast, but worst hit was the Greek island of Kos, where both confirmed deaths occurred, along with most of the injuries reported. So far, officials say more than 120 people have been wounded.

Associated Press reports:

Fallen bricks and other debris coated many streets, and the island’s seafront road and parts of the main town were flooded.

Giorgos Hadjimarkos, the regional governor, said four or five of the injuries were “worrying” and damaged buildings were being inspected, but the “main priority at the moment is saving lives”.

The Kos hospital said at least 20 of the injured had broken bones.

A wall collapsed on a building dating to the 1930s and crushed people who were at the bar in the building’s lower level, according to Kos mayor Giorgos Kyritsis.

“There are not many old buildings left on Kos. Nearly all the structures on the island have been built under the new codes to withstand earthquakes,” the mayor said.

Kos’s old town area, full of bars and other nighttime entertainment, was littered with broken stone in the streets. Hotels had shattered glass and other damage, leaving hundreds of tourists to spend the rest of the night outdoors, trying to sleep on beach loungers with blankets provided by staff.

The European-Mediterranean Seismological Centre (EMSC), which monitors earthquakes in the region, has issued advice for those affected by the quake and its aftershocks:

Many holidaymakers have been affected as the quake has struck areas in Greece and Turkey that are brimming with tourists in July.

Package holiday firm Thomas Cook has just issued a statement:

Thomas Cook is aware of the earthquake which occurred off the coast of Turkey and Greece, and we are working hard to support all our customers and staff in resort.

We will provide an update as soon as we have further information.

The two people killed in Kos were foreigners, the island’s mayor, Giorgos Kyritsis has told Greece’s Skai radio.

They have not been identified, but reports have said they were killed when the ceiling of a building collapsed on to them.

It’s now daylight in the affected areas – the quake struck at 1.30am local time – and many people are still sleeping outside, unable to return to their homes or hotel rooms.

The quake has struck at the start of the peak tourist season for Kos and Bodrum, with many travellers expected to arrive from other European countries in the coming weeks.

This Saturday would typically be one of the busiest weekends for arrivals.

It’s not yet clear to what extent the quake will affect arrivals to and departures from the quake-hit areas. Ferries to Kos have been suspended.

Two arrival flights from Athens to Kos and two departure flights from Kos to Athens have been cancelled. However, flights later in the day are currently scheduled as normal.

Eleanor Ruddock and her 22-year-old daughter Naomi, who are holidaying at the Akti Palace resort in Kardamena, on the island of Kos, told Press Association they woke to their room shaking and immediately grabbed their phones and ran outside.

Naomi Ruddock told PA:

We were asleep and we just felt the room shaking. The room moved. Literally everything was moving. And it kind of felt like you were on a boat and it was swaying really fast from side to side, you felt seasick.

She said that while hotel staff had been pleasant, they had not received official information about what they should do.

The restaurant manager just said that he’s never seen anything like this ever happen ever around this area or ever in Greece. He said it was like something out of a film, and it was.

The people I have talked to on Kos all say there have been many strong aftershocks.

Rebecca Reeve, a student social worker from south-east England, is staying at the Mitsis Family Village beach hotel on the south of Kos. She told the Guardian:

Tremors are very frequent … last one a few mins ago. [It was] very strong.

In Turkey, Briton Graham W is staying two bays to the east of Bodrum, in the town of Bitez. He said the earthquake was “extremely scary”:

Everyone [is] asleep around the pool. Hotel handed blankets out.

He said the aftershocks there had been “violent but quick”.

Officials in Bodrum say there have been injuries but no deaths in the Turkish resort.

But many residents and tourists have fled buildings to sleep outside, or – as dawn arrives – wander the streets.

Mehmet Kocadon, the city’s mayor, told NTV television:

The biggest problem at the moment are electricity cuts in certain areas.

There is light damage and no reports that anyone has been killed.

There are reports via AFP news agency that the state hospital in Bodrum was evacuated after cracks appeared, with incoming patients being examined in a garden outside.

Bodrum’s Adliye mosque also suffered damage and has been cordoned off.

There was also flooding of coastal roads after the quake triggered high waves.

ITV News has some video of staff fleeing a restaurant in Bodrum as the quake hits:

Reuters reports that Greek authorities have dispatched helicopters to Kos to airlift the injured to the larger island of Rhodes for treatment, citing Yiorgos Hadjimarkou, the head of the South Aegean region.

“Our primary concern right now is [safeguarding] human life,” Hadjimarkou told Greek state broadcaster ERT.

Tom Riesack from Germany is staying on Kos in a resort called Astir Odysseus, with his wife and nine-year-old twins. He told the Guardian:

We were literally shaken out of our beds from deep sleep. The whole room was shaking and we fled the room into the open.

Thankfully I am staying in a newer hotel that has been built ‘earthquake safe’.

Smaller aftershocks have been felt since the first big tremor, he said:

We have just had another big tremor … bigger than the last aftershocks. [It’s] scary.

Riesack said he had walked down to the beach to see if there was any damage:

There had been some flooding of up to 1m, which moved some of the deckchairs and the like. [There was] no damage that I could see, apart from some flower pots toppled over.

Overall the hotel looks good compared to the photos from Kos.

The United States Geological Survey (USGS), which monitors earthquakes, said the strong quake was very shallow – only 10km (6.2 miles) below the seabed – and located off the southwestern coastal city of Marmaris in the Mugla province of Turkey.

The epicentre was just 10km south of the Turkish resort of Bodrum and 16km east-northeast of Kos.

Updated figures from Kos now suggest at least 120 people were injured on the island.

Earlier reports said around 70 people were injured in Turkey.

Two people have been confirmed dead in Kos.

Pictures from the scene show damage to buildings and, in some coastal areas, flooding after sea levels rose in the wake of the mainshock.

Kos

Bodrum

The quake has affected an area popular with tourists from many countries.

The UK foreign office has warned of travellers to be careful of aftershocks. A spokesman said:

We are speaking to the Turkish and Greek authorities following an earthquake off the coast of Bodrum and near the island of Kos.

Any British people in the areas affected should follow the instructions of local authorities.

A hotel worker at the 1-2-FLY Fun Club, on the western side of Kos, told the Guardian that the earthquake was the largest he had ever felt:

When the first shock came, everybody was scared. Guests immediately came out of their rooms.

We’ve asked all the guests to wait outside because there have been 11 or 12 aftershocks.

One of the hotel guests, Rolf Schwarz, 50, was on holiday with his family. Guests had been advised “it was better to spend the rest of the night outside”, he told the Guardian from the pool area of the hotel. The building appeared to have suffered no damage, he added.

At the beach, Schwarz said he had seen what he described as a “mini-tsunami”, where the water level rose temporarily.

The chairman of Turkey’s disaster and emergency management presidency (AFAD), Mehmet Halis Bilden, told broadcaster CNN Turk that people in the area needed to be prepared for aftershocks:

Our people should know that aftershocks are continuing, so they should refrain from entering damaged or vulnerable structures.

AFAD said it had observed at least 20 aftershocks across Turkey and Greece following the mainshock at 1.31am local time on Friday (22.31 GMT on Thursday). At least five of the aftershocks registered over 4.0 magnitude, with the largest so far at 4.6.

A magnitude 6.7 quake is considered strong and is capable of causing considerable damage, but the effects of this one would have been lessened by striking in the sea.

Michael Heckmann from Germany is on holiday on the Greek island of Kos with his wife and four children, aged 10, eight, five and one. They are staying in the Blue Lagoon hotel on the north of the island, about 4km inland. He told the Guardian:

It was very scary – the whole room was shaking when the earthquake hit. We were woken up when the beds were shaking and bending. When I stood up I was still being shaken and the whole room seemed to be moving around. It was really frightening.

I woke up all my kids and told them we had to get outside. It was my first earthquake and was very scary. Everybody got out of the hotel and we stayed outside the buildings for about an hour and then the hotel management told us it was safe to go back into the buildings.

There have been aftershocks – even a few minutes ago – but they are much smaller than the original quake.

Heckmann said he was thankful that he was staying in a solid building.

At this early stage – it is not yet dawn in the area – reports of injuries are still unclear and sometimes conflicting.

The mayor of Kos, George Kyritsis, confirmed that two people had been killed, telling Reuters:

We have two dead and some people injured so far.

The island’s main hospital said 20 people were injured, though other sources put the number higher at at least 30, including at least two tourists. There are reports that the roof of a bar in Kos collapsed, injuring several.

Damage has also been reported to the port of Kos; ferries would not be docking there, the coast guard said.