In late June, Wagner mercenary leader Yevgeny Prigozhin took control of Russia’s southern city of Rostov-on-Don, the opening salvo of a mutiny against the Kremlin that ended in a fragile truce orchestrated by Belarus’s leader Alexander Lukashenko.

The uprising was a public humiliation for Russian President Vladimir Putin, a leader believed to have a long history of taking out those he perceives as traitors.

Many believed Prigozhin’s days were numbered.

Two months later, a private Embraer jet travelling from Moscow to St Petersburg crashed on August 23 north of the capital, killing Prigozhin and nine other people on board, including Dmitry Utkin and Valery Chekalov, four bodyguards and a crew of three.

But different theories as to why the jet crashed abound, with Moscow and Washington both suggesting foul play. Here is what has been said:

Possible ‘deliberate atrocity’: Kremlin

The Kremlin said on Wednesday that investigators were considering the possibility that the Plane carrying Prigozhin was downed on purpose, the first explicit acknowledgement that he may have been assassinated.

“It is obvious that different versions are being considered, including the version – you know what we are talking about – let’s say, a deliberate atrocity,” Kremlin spokesperson Dmitry Peskov told reporters when asked about the investigation.

Asked if the International Civil Aviation Organization would investigate the crash, Peskov said that the circumstances made it different, though he cautioned that investigators had made no formal conclusions yet about what exactly took place.

“Let’s wait for the results of our Russian investigation,” Peskov said.

Asked about that report, Peskov said: “First of all, the investigation is under way, the Investigative Committee is engaged in this.”

“In this case, there can be no talk of any international aspect,” Peskov said.

In an unusual move, the Interstate Aviation Committee (IAC), which oversees aviation accident investigations in a grouping of former Soviet republics, including Russia, said it was not investigating the crash, adding that it would not be commenting on the “circumstances of the incident”.

The Kremlin has rejected as an “absolute lie” the suggestion by some Western politicians and commentators – for which they have not provided evidence – that Putin ordered Prigozhin to be killed in revenge.

Intentional explosion likely caused crash: Washington

A preliminary US intelligence assessment concluded that an intentional explosion caused the plane crash.

One of the US and Western officials who described the initial assessment said it determined that Prigozhin was “very likely” targeted and that the explosion falls in line with Putin’s “long history of trying to silence his critics”.

Pentagon spokesperson General Pat Ryder said press reports that a surface-to-air missile took down the plane were inaccurate. He declined to say whether the US suspected a bomb or believed the crash was an assassination.

FSB ‘most likely’ behind plane crash: British security sources

Shortly after the crash, British security sources told the BBC that Russia’s Federal Security Service, the FSB, was “most likely to have targeted Yevgeny Prigozhin’s plane”.

UK defence sources tell BBC: Prigozhin’s plane most likely brought down by Russia’s FSB domestic intel agency. Likely to strengthen position of Prigozhin’s enemies: Shoigu and Gerasimov. #Prigozhin

— Frank Gardner (@FrankRGardner) August 24, 2023

The UK’s Secret Intelligence Service, the MI6’s former head, Richard Dearlove, also told the Telegraph newspaper that Prigozhin’s death was “unsurprising”.

“I’m sure it’ll be presented as an accident, and there will be an element of doubt, but everyone in the West will come to the same conclusion – that this is Putin’s revenge on people who challenge his power base,” he added.

Air defences hit plane: pro-Wagner Telegram channel

Prigozhin supporters claimed on pro-Wagner channels of Telegram messaging app that the plane was deliberately downed.

A post by Grey Zone, a Wagner-connected social media channel, claimed Russian anti-aircraft defences had shot down the plane.

It said that residents heard “two bursts of characteristic air defence fire” before the crash.

“This is confirmed by inversion traces in the sky in one of the videos,” it added.

Eyewitness accounts report explosion before crash

The plane crashed near the village of Kuzhenkino in Russia’s Tver region.

Kuzhenkino resident Vitaly Stepenok, 72, told the Reuters news agency: “I hear an explosion or a bang. Usually, if an explosion happens on the ground, then you get an echo, but it was just a bang, and I looked up and saw white smoke.”

“One wing flew off in one direction, and the fuselage went like that,” he said, gesturing with his arms to show how the plane headed down towards the ground.

“And then it glided down on one wing. It didn’t nose-dive, it was gliding.”

Another villager named Anatoly said: “In terms of what might have happened, I’ll just say this: It wasn’t thunder; it was a metallic bang. Let’s put it that way, I’ve heard things like that before.”

Aircraft ascended, descended several times before crash: Flightradar24

Flightradar24, a Swedish internet-based service that shows real-time aircraft flight tracking information, released a report on the plane crash that showed the aircraft had struggled to maintain altitude before it plummeted to the ground.

“Even though the aircraft was not transmitting position information, other data like altitude, speed, vertical rate, and autopilot settings were broadcast. It is this data that provides some insight into the final moments of the flight,” the report stated.

Flightradar24 says that after levelling off at 28,000 feet (8,534 metres) at 6:10pm (15:10 GMT), the aircraft continued in level flight at consistent speed until 6:19pm (15:19 GMT), at which point the vertical rate decreased dramatically causing the aircraft to descend briefly before climbing to a maximum altitude of 30,100 feet (9,174 metres) and then dropping to about 27,500 feet (8,382 metres).

Flightradar24 says the plane then climbed once more reaching 29,300 feet (8,931 metres) and levelling off once again before eventually spiralling into a fall to the ground.