Russian President Vladimir Putin says his friend-turned-foe Yevgeny Prigozhin was a man with “a difficult fate” who made “serious mistakes in life” in his first public comments since the fatal plane crash.

Mr Putin expressed his “most sincere condolences” to the families of all ten victims on the business jet that plunged from the sky with no survivors.

“It is always a tragedy,” he said in televised remarks from the Kremlin.

The US Pentagon on Friday morning (AEDT) confirmed that Prigozhin was “likely killed” in the crash.

But US Defence Department spokesperson Brigadier General Patrick Ryder said nothing indicated that a surface-to-air missile downed the flight.

Wagner-linked Telegram, Grey Zone, earlier claimed the plane had been shot down by the Russian military amid witness reports of two explosion sounds before it fell.

Some unnamed sources told Russian media they believed the plane was shot down by surface-to-air missiles.

The Baza news outlet, which has good sources among law enforcement agencies, reported that investigators were focusing on a theory that one or two bombs may have been planted on board.

Responding to reports that other members of the Wagner group were on the jet, Mr Putin said “we will not forget” their contribution to fighting “neo-Nazis” in Ukraine.

Mr Putin said he had known Prigozhin since the 1990s in the immediate aftermath of the collapse of the Soviet Union.

At the time Prigozhin was a convicted criminal who went on to establish a successful catering company before founding the Wagner mercenary group.

“He was a talented person, a talented businessman, he worked not only in our country, and worked with results, but also abroad, in Africa in particular.”

Mr Putin mentioned that Prigozhin had just returned to Russia the previous day from Africa and had met with officials.

The plane had been on its way from Russia to St Petersburg when it spiralled from altitude and crashed on the outskirts of a village in the Tver region, northwest of Moscow.

Crash investigators have still to conclusively identify the remains of the 10 people believed to have died in Wednesday’s crash northwest of Moscow, and Mr Putin said the examination would take time.

The crash occurred exactly two months after Prigozhin led a mutiny against Russia’s army leadership, a act of rebellion that Mr Putin at the time condemned as a treacherous “stab in the back”.

Tributes to Yevgeny Prigozhin (L) and Dmitry Utkin (R), who managed Wagner’s operations, at a makeshift memorial in front of the PMC Wagner office in Novosibirsk. Photo: Getty

Russian investigators opened a criminal probe but there has been no official word on what may have caused Wednesday evening’s crash.

Until Mr Putin’s comments there had been no official confirmation of Prigozhin’s death beyond a statement from the aviation authority saying he was on board.

A Reuters reporter at the crash site saw men carrying away black body bags on stretchers.

Part of the plane’s tail and other fragments lay on the ground near a wooded area where forensic investigators had erected a tent.

The plane wreckage near the village of Kuzhenkino, Tver region. Photo: Getty

Mr Prigozhin, 62, was head of the Wagner mercenary group and a self-declared enemy of the army top brass over what he said was its incompetent prosecution of Russia’s war in Ukraine.

State media gave the plane crash low-key coverage.

The Embraer Legacy 600 executive jet was reported to have also been carrying senior members of Prigozhin’s team.

Prigozhin spearheaded the mutiny against the army leadership on June 23-24 which Putin said could have tipped Russia into civil war.