The officials, who spoke on condition of anonymity given the sensitivity of the matter, stressed that the information was still preliminary and under review.
Prigozhin was on the passenger manifest of the Embraer private jet that crashed on Wednesday in the Tver Region, en route from Moscow to St. Petersburg. All seven passengers and three crew members perished.
Authorities are still working to identify the bodies, but Prigozhin is presumed to be among them, along with six other Wagner leaders.
The New York Times has also reported that American and other Western officials has stated an explosion on the plane likely brought down the aircraft.
A definitive conclusion has not been reached, but an explosion is the leading theory of what caused the plane to crash in a field between Moscow and St. Petersburg. The blast could have been caused by a bomb or other device planted on the aircraft, though other theories, like adulterated fuel, were also being explored, the officials said.
The incident happened exactly two months after Wagner’s failed mutiny against the Russian military. Prigozhin had accused the Russian Defense Ministry of attacking a Wagner base and sent a convoy of troops toward Moscow, while taking over the military command post in Rostov-on-Don.
Russia President Vladimir Putin condemned the mutiny as tantamount to treason and had a criminal case opened against Prigozhin. The charges were dropped within days, however, as Prigozhin agreed to disband much of Wagner and leave with the rest to Belarus and Africa, as part of a deal brokered by Belarusian President Alexander Lukashenko.