“Deliberate wrongdoing” is among the possible causes of the plane crash that killed Russian mercenary leader Yevgeny Prigozhin last week, the Kremlin’s spokesperson said on Wednesday.

Speaking to reporters during his daily conference call, presidential press secretary Dmitry Peskov said “different versions” of what happened exist and “are being considered” by Russian investigators, including, “let’s put this way - deliberate wrongdoing”.

A business jet carrying Prigozhin, the founder and leader of the private military force Wagner Group, and his top lieutenants crashed halfway between Moscow and St. Petersburg a week ago, killing all seven passengers and three crew members on board.

The Interstate Aviation Committee, the Moscow-headquartered body that oversees civil aviation in most former Soviet republics, said in an online statement on Wednesday it was not currently investigating the crash, although the agency has an accident investigation division.

Peskov said there can’t be an international investigation into why the plane plummeted from the sky, and he urged reporters to wait for the Russian Investigative Committee to complete its review. The committee said last week it opened a criminal case to look into possible flight safety violations, a standard procedure in Russia when there is no immediate reason to suspect foul play.

A police officer takes pictures of the grave of Wagner Group chief Yevgeny Prigozhin after a funeral at Porokhovskoye Cemetery in St. Petersburg. Photo / AP

The crash occurred exactly two months after Prigozhin mounted a short-lived armed rebellion against Russia’s military leadership, posing the biggest challenge to Russian President Vladimir Putin’s authority in his 23-year rule. The Kremlin has denied involvement in the crash.

Prigozhin, 62, was buried in St. Petersburg, his hometown, in a private ceremony that was shrouded in secrecy until Tuesday evening, when his spokespeople revealed the location of his grave.

Western officials and analysts expect the private Wagner army to continue operating, particularly in the Sahel region of Africa, where Russian mercenaries have provided security against extremist organizations like al-Qaeda and the Islamic State group.

• Putin breaks silence on Prigozhin's plane crash; US reveals more details on explosion
• Russia confirms Wagner leader Prigozhin killed in plane crash
• UoO international relations expert: Prigozhin needs to be wary after failed mutiny
• Questions surround death of Yevgeny Prigozhin after he 'showcased Putin's weakness'

A young woman lights a candle as others stand at an informal street memorial with flowers and lit candles for members of the mercenary Wagner Group killed in a plane crash. Photo / AP

“I am sure they’ll find a replacement” for Prigozhin, European Union foreign policy chief Josep Borrell said on Wednesday after chairing talks among EU defence ministers.

“Wagner will continue to operate in the service of Putin in Africa, doing what they do, which is not contributing to peace in the Sahel or the defence of the rights of Saharan Africans,” Borrell said.

Africa is vitally important to Russia — economically and politically.

This summer, Wagner helped secure a national referendum in the Central African Republic that cemented presidential power; it is a key partner for Mali’s army in battling armed rebels; and it contacted the military junta in Niger that wants its services following a coup.

Expanding ties and undercutting Western influence in Africa is a top priority as the Kremlin seeks new allies during its war in Ukraine, where Wagner fighters helped Russia win a long and bloody battle for the city of Bakhmut.

Africa’s 54 nations are the largest voting bloc at the UN, and Moscow has actively worked to rally their support for its invasion.