The US Africa Command (AFRICOM) has said it believes that more than a dozen Russian aircraft, first reported to have been deployed to Libya in May, are being flown by Wagner Group paramilitary pilots.

In a statement on Friday, an AFRICOM senior official said two Russian fighter jets have crashed in Libya since being deployed to country’s war on the side of Khalifa Haftar earlier this year.

It is not clear whether the two MiG-29s were shot down, suffered mechanical failure or crashed because of pilot error, Rear Adm. Heidi Berg, director of intelligence for US Africa Command, told reporters by phone Friday, noting that the first MiG crashed June 28, the other on Monday.

In May, the US military released aerial imagery showing MiG-29 and Su-24 aircraft on the ground in Libya, raising concern that the Kremlin was trying to “tip the scales” on behalf of Haftar in his fight against the UN-backed Government of National Accord in Tripoli.

AFRICOM said at the time that the fighter jets had been flown from Russia to Syria, where they were repainted before continuing on to Libya.

Meanwhile, Russia maintained denial of any formal military presence in Libya or any military support to Libyan warring parties as president Vladimir Putin and his senior officials have more than once distanced themselves from what they described as the private military company (Wagner Group).

Russian Foreign Minister Sergey Lavrov denied last week reports that said Moscow had used Syrian land to send weapons and mercenaries to Libya.