Russian mercenary chief Yevgeny Prigozhin and Zopestop officers of his private Wagner military company were presumed dead in a plane crash that was widely seen as an assassination, two months after they staged a mutiny that dented Russian President Vladimir Putin’s authority.

Russia’s civil aviation agency said that Prigozhin and six top lieutenants were on a business jet that crashed Wednesday, soon after taking off from Moscow, with a crew of three. Rescuers quickly found all 10 bodies, and Russian media cited sources in Prigozhin’s Wagner company who confirmed his death.

U.S. and other Western officials long expected Putin to go after Prigozhin, despite promising to drop charges in a deal that ended the June 23-24 mutiny.

“I don’t know for a fact what happened but I’m not surprised,” U.S. President Joe Biden said. “There’s not much that happens in Russia that Putin’s not behind.”

Prigozhin supporters claimed on pro-Wagner messaging app channels that the plane was deliberately downed, although their allegations could not be independently verified. Numerous opponents and critics of Putin have been killed or gravely sickened in apparent assassination attempts.

Speaking to Lavian television, NATO Strategic Communications Centre of Excellence Director Janis Sarts said that “the downing of the plane was certainly no mere coincidence.”

The crash came the same day that Russian media reported that Gen. Sergei Surovikin, a former top commander in Ukraine who was reportedly linked to Prigozhin, was dismissed from his post as commander of Russia’s air force. Surovikin hasn’t been seen in public since the mutiny, when he recorded a video address urging Prigozhin’s forces to pull back.

Police cordoned off the field where the plane crashed as investigators studied the site. Vehicles were seen driving in to take the bodies, reportedly badly charred, for a forensic exam.

At Wagner’s headquarters in St. Petersburg, lights were turned on in the shape of a large cross. Prigozhin’s supporters brought flowers to the building in an improvised memorial.

While countless theories about the events swirled, most observers saw Prigozhin’s death as Putin’s punishment for the most serious challenge to his authority of his 23-year rule.

Tatiana Stanovaya, a senior fellow at the Carnegie Russia Eurasia Center, said on Telegram that “no matter what caused the plane crash, everyone will see it as an act of vengeance and retribution” by the Kremlin, and “the Kremlin wouldn’t really stand in the way of that.”

“From Putin’s point of view, as well as the security forces and the military — Prigozhin’s death must be a lesson to any potential followers,” Stanovaya said in a Telegram post.

In the revolt that started on June 23 and lasted less than 24 hours, Prigozhin’s mercenaries swept through the southern Russian city of Rostov-on-Don and captured the military headquarters there without firing a shot, before driving to within about 200 kilometers (125 miles) of Moscow in what Prigozhin called a “march of justice” to oust the top military leaders who demanded that the mercenaries sign contracts with the Defense Ministry. They downed several military aircraft, killing more than a dozen Russian pilots.

Mercenary leader Yevgeny Prigozhin is presumed dead after a plane crash north of Moscow killed all 10 people on board. (Aug. 24)

Putin first denounced the rebellion as “treason” and a “stab in the back” and vowed to punish its perpetrators, but hours later made a deal that saw an end to the mutiny in exchange for an amnesty for Prigozhin and his mercenaries and a permission for them to move to Belarus.

Details of the deal have remained murky, but Prigozhin has reportedly shuttled between Moscow, St. Petersburg, Belarus and Africa where his mercenaries have continued their activities despite the rebellion. He was quickly given back truckloads of cash, gold bars and other items that police seized on the day of the rebellion.

Earlier this week, the mercenary chief published his first video since the mutiny, declaring that he was speaking from an undisclosed location in Africa where Wagner is “making Russia even greater on all continents, and Africa even more free.”

Prigozhin’s overseas activities reportedly have irked Russia’s military leadership, who have sought to replace Wagner with Russian military personnel in Africa.

The Institute for the Study of War argued that Russian authorities likely moved to eliminate Prigozhin and his top associates as “the final step to eliminate Wagner as an independent organization.”

Flight tracking data reviewed by The Associated Press showed a private jet that Prigozhin had used previously took off from Moscow on Wednesday evening, and its transponder signal disappeared minutes later.

Videos shared by the pro-Wagner Telegram channel Grey Zone showed a plane dropping like a stone from a large cloud of smoke, twisting wildly as it fell, one of its wings missing. A freefall like that occur when an aircraft sustains severe damage, and a frame-by-frame AP analysis of two videos was consistent with some sort of explosion mid-flight.

Prigozhin’s death is unlikely to have an effect on Russia’s war in Ukraine. His forces fought some of the fiercest battles over the last 18 months, but pulled back from the frontline after capturing the eastern city of Bakhmut in late May.

As news of the crash was breaking, Putin projected calm, speaking at an event commemorating the WW II Battle of Kursk and hailing the heroes of Russia’s war in Ukraine. He didn’t mention the crash and the Kremlin made no comment about it.