Aug. 23 (UPI) -- Wagner Mercenary Group leader Yevgeny Prigozhin was on the passenger list of a private jet that crashed in Russia on Wednesday, killing all 10 people aboard, Russian officials said.
All aboard the Embraer plane -- seven passengers and three crew -- were killed, the Federal Air Transport Agency said. The plane hit the ground and caught on fire in the Russia's Tver region, where the plane was flying from Moscow to St. Petersburg.
Pilot Aleksei Levshin, co-pilot Rustam Karimov and flight attendant Kristina Raspopova, were identified and listed as having been onboard.
The Federal Air Transport Agency said it has launched an investigation into the crash.
Prigozhin, 62, led his forces in a mutiny against the Russian military on June 23-24, marching within miles of Moscow before retreating.
Earlier Wednesday, Russian media reported that the former head of Russian forces in Ukraine, Gen. Sergei Surovikin, was relieved of his duties as chief of Russia's Air Force because of his alleged close ties to Prigozhin.
"The head of the Wagner Group, Hero of Russia, a true patriot of his Motherland -- Yevgeny Victorovich Prigozhin died as a result of the actions of traitors to Russia. But even in Hell he will be the best! Glory to Russia," Grey Zone posted to Telegram Wednesday.
The channel suggested Wagner would retaliate.
"The assassination of Prigozhin will have catastrophic consequences," Grey Zone said in a post Wednesday.
U.S. officials said the death was a consequence of the war in Ukraine.
"If confirmed, no one should be surprised. The disastrous war in Ukraine led to a private army marching on Moscow, and now -- it would seem -- to this," White House national security spokesperson Adrienne Watson said.
U.S. President Joe Biden said he was "not surprised" to hear of Prigozhin's demise.
"There's not much that happens in Russia that Putin's not behind, but I don't know enough to know the answer," Biden told reporters.
Shortly after the crash, Putin appeared in public for a commemoration ceremony marking 80 years since the Battle of Kursk in World War II.
"They were stopped and driven back to their already inevitable, inevitable collapse," Putin said in reference to the German forces that were defeated in the decisive battle.
Putin also referred to the war in Ukraine, which the Russian government still calls a "special military operation."
"Devotion to the Motherland, loyalty to the military oath unite all participants in the special military operation," Putin said.