Russian leader says grenade fragments found in bodies of those killed in jet crash where Wagner’s Yevgeny Prigozhin died.

Putin suggested on Thursday that Prigozhin’s plane was blown up from the inside, not hit by a missile as rumoured, saying that the head of Russia’s investigative committee had reported that traces of explosives were discovered in the bodies of those who died in the crash in August.

“Fragments of hand grenades were found in the bodies of those killed in the crash,” Putin told a meeting of the Valdai Discussion Club in the Black Sea resort of Sochi.

“There was no external impact on the plane – this is already an established fact,” Putin said, appearing to rubbish claims by US officials who believed the plane was shot down.

The private Embraer jet on which Prigozhin was travelling to St Petersburg crashed north of Moscow killing all 10 people on board on August 23. Two other top Wagner figures, Prigozhin’s four bodyguards and a crew of three were also killed.

Putin did not give any more details about how a grenade or grenades could have been detonated on board the executive jet, but said he thought investigators were wrong not to have carried out alcohol and drug tests on the bodies of those who died in the crash.

“In my opinion, such an examination should have been carried out, but it was not,” Putin said.

Putin also claimed that searches of Wagner’s offices in St Petersburg after the crash turned up 10 billion roubles ($100m) in cash and 5kg (11 pounds) of cocaine.

The investigators of the crash have yet to report publicly on their findings. Moscow rejected an offer from Brazil, where the Embraer business jet was built, to join the crash inquiry.

Prigozhin died in the crash exactly two months to the day after leading a short-lived mutiny against Russia’s defence establishment and presented the biggest challenge to Putin’s rule since he came to power in 1999.

A preliminary US intelligence assessment concluded that an intentional explosion caused the crash, and Western officials have pointed to a long list of Putin foes who have been assassinated.

The Kremlin has rejected as an “absolute lie” the suggestion that Putin had Prigozhin killed in revenge for the rebellion by the Wagner private army.

The fate of Wagner has been unclear since Prigozhin’s death.

Putin has ordered Wagner fighters to sign contracts with Russia’s defence ministry, a move which Prigozhin and many of his men had opposed.

When asked about the future of so-called private military companies in Russia, Putin said on Thursday that as there had been no law on such groups, the experience of them in Russia had been “clumsy”.

“We do not yet have a consensus in Russia about whether we need such formations or not, but today I can say for sure that several thousand fighters of this company have already signed contracts with the armed forces,” Putin said.

Before his death, Prigozhin had accused Russia’s military leaders,  particularly Defence Minister Sergei Shoigu and Chief of General Staff Valery Gerasimov, of incompetence and warned that Russia could lose the war in Ukraine unless it raised its game.

After his death, Putin described the Wagner chief as a man who had made “serious mistakes in his life but he achieved the right results”.

The Wagner Group mercenary force that Prigozhin created was active in Ukraine, Syria, Libya and several African countries and counted tens of thousands of fighters at its peak.

Sanctioned by the European Union and the US for gross human rights abuses in the countries where Wagner deployed, the force played a key role in the fighting in Ukraine, where it spearheaded the capture of the eastern Ukrainian city of Bakhmut in May after months of bloody combat.