Ghassan Abu Sitta, a British-Palestinian surgeon treating injured survivors of bombings in Gaza, received an alarming call from London this week that counter-terrorism officers had visited his home.

Abu Sitta, who volunteers with Doctors without Borders and is still in the besieged enclave, told the BBC the visit was a “kind of brutish attempt at harassment and silencing” and said he was seeking legal advice. 

The Metropolitan police confirmed they had “attended an address in north London” in response to reports that a man was “planning to go to a war zone”.

Ripple effects from the war between Israel and Hamas are being felt by Muslim and Arab populations across Europe, who fear an Islamophobic backlash. They worry that the conflict and recent Islamist attacks in France and Belgium are emboldening far-right voices who cast Muslims and Arabs as a fifth column posing a danger from within.

“Muslims are really afraid of being stigmatised and blamed, and lumped together with Hamas supporters,” said Lamya Kaddor, a German MP with Syrian roots. “They worry about becoming strangers in their own country.”

Such concerns were heightened by the news last weekend that a six-year-old boy, Wadea Al-Fayoume, was stabbed to death in the US, reportedly because he was a Muslim. A 71-year-old man was subsequently charged in Illinois with murder and hate crimes.

In Europe, some Muslims and Arabs said they were being scapegoated for expressing solidarity with the Palestinians because the UK and EU countries had taken a staunch pro-Israel stance; they lamented the lack of empathy over civilian deaths in the bombardment of Gaza.

In France — home to the biggest Jewish and Muslim populations in Europe — such frustrations only grew when authorities imposed a nationwide ban on all pro-Palestinian demonstrations, a move they said was designed to “protect public order”. Critics challenged the ban in court as an illegal curb on free speech and won their case on Wednesday. Local officials who report to the interior ministry will now decide on a case-by-case basis whether such protests can be held.

“Banning protests just increases the feeling of frustration and injustice that many Muslims are feeling,” said Tareq Oubrou, an imam in Bordeaux.

The return of so-called lone wolf attacks carried out by Islamist extremists has exacerbated a tense situation. In northern France, a young Chechen stabbed a teacher to death at a secondary school on Friday, and in Brussels, two Swedish citizens were gunned down by a Tunisian man on Monday night. Both perpetrators declared their support for the jihadist group Isis in videos, police said. 

Ministers and the federal prosecutor in Belgium have said the gunman who attacked Swedes in Brussels was likely motivated by a series of Koran burnings carried out in the Scandinavian country in recent months by anti-Islam activists.

Hugo Micheron, an academic at Sciences Po who researches jihadism in Europe, said that a potentially turbulent period had begun, in which the impacts of conflicts in the Middle East could again have spillover effects in Europe. There is a risk both of increased Islamist attacks and of blowback against Muslim and Arab minorities.

“This is the trap that Islamism opens up for western democracies. They seek to divide societies,” he said. “Muslim citizens in Europe are under pressure, and we cannot be blind to that.” 

Although there are few official statistics, Muslim organisations are reporting an alarming uptick in racist rhetoric, both online and off. In the UK, Tell Mama, a charity that records cases of Islamophobia, said on Monday it had catalogued 200 incidents nationally since the Hamas attack on Israel, a fivefold increase over the same period in 2022. 

In one incident on a train outside London that is under police investigation, a Muslim woman had her hijab torn off and received death threats. 

Aiman Mazyek, head of the Central Council of Muslims in Germany, said the “verbal violence” directed at community leaders like him had “massively increased in the past few days”.

He cited the online reaction to his statement condemning Hamas’s attack on Israel. Mazyek said one person wrote, with reference to Muslims: “I’d throw these bastards out of the country or just hang them up from the nearest tree.”

Others complained of police harassment. “In areas of Berlin with big Arab populations . . . we’re seeing an increase in police checks carried out on people perceived to be Muslim, without any reasonable suspicion,” said Rima Hanano of CLAIM, a group that campaigns against anti-Muslim racism. “That clearly constitutes racial profiling.”

In the south German town of Regensburg, the febrile mood claimed a victim last Friday when a young Syrian was seriously injured after being deliberately pushed off a bridge. His attacker, who has been charged with attempted murder, was a rightwing extremist long known to authorities.

But it was the killing of six-year-old Wadea Al-Fayoume in the US that really sent shockwaves through Europe, said community leaders. It “shows how entrenched the front lines are becoming”, said Kaddor.

She said she was sure such an incident could happen in Germany. “Attacks on Muslims are an almost daily occurrence here.” 

In France, tensions are particularly high because previous flare-ups of the Israeli-Palestinian conflict were followed by antisemitic incidents domestically.

In a televised address on Thursday last week, President Emmanuel Macron declared France’s support for Israel’s right to defend itself against Hamas, and also called for “national unity” so as to avoid adding “domestic divides to international divides”.

He sought balance as he reassured Jewish citizens that the state would protect them, while recognising the worry felt by “our Muslim compatriots” who also fear discrimination.

Yet soon after Macron spoke, a 20-year-old assailant killed the teacher in Arras, reviving old traumas in France, which has experienced multiple deadly Islamist attacks in recent years, including the decapitation of another teacher in 2020.

Far-right politicians attacked what they cast as the government’s lax security and immigration policy. “Stop immigration . . . let’s cede not one more centimetre to the Islamisation of our country,” said one-time presidential candidate Éric Zemmour. 

The distrust is affecting the private sphere. In a Paris suburb this week, a Muslim mother of three was detained by police for five hours after a conflict with a neighbour degenerated into duelling police complaints, according to her lawyer Nabil Boudi.

In his telling, the neighbour reported his client for speaking in Arabic to workers in the building, interpreting “salam alaikum” and other phrases as threatening, and telling her she should be ashamed to be speaking Arabic given “all that was going on in Israel”.

“It is crazy that such a thing would happen,” said Boudi. 

The neighbour alleged that Boudi’s client made threats against her, according to a police report reviewed by Liberation newspaper.

In Sweden, Mohannad Yousif, a 45-year-old who has helped organise pro-Palestinian rallies in Malmö, wants to ensure that his voice and that of fellow protesters are not only heard but understood by fellow Swedes, so they decided to ban chanting in Arabic.

Yousif, who moved to Sweden from Lebanon as a child in 1986, said he expected anti-immigration parties to use tensions during the war between Hamas and Israel “in the negative direction”. But he said this was nothing new: “The far-right has always been telling us that we are all terrorists and that we should go home to ‘our own’ countries.”