A European official said Tuesday that between 10.000 and 20.000 mercenaries from the Russian Wagner Group and fighters from Syria and Libya are currently fighting alongside the Russian forces in Ukraine.

According to the US-based Al-Hurra website, the official who asked not to be named, explained that those mercenaries do not have vehicles or heavy weapons, saying “they were brought in by Russia to support its forces in its invasion of its neighbor.”

“Transfer of fighters has been detected from countries like Syria and Libya, to the Donbass region in eastern Ukraine,” the official said, adding that Russia has recently launched a new phase of its offensive in that region.

The European official pointed out that it is difficult to determine how many of those men are mercenaries from the private Wagner Group, Libyan or Syrian fighters.

Late in last March, the British Ministry of Defense indicated that "more than 1,000 mercenaries" from Wagner, including company officials, were deployed in eastern Ukraine in order to "carry out combat operations", as the West accuses this Russian paramilitary group of being close to the Kremlin and committing violations in Mali, Libya and Syria.

The Ukrainian Defense Ministry announced earlier that there was an agreement between Khalifa Haftar, a Libyan self-styled military commander based in the east, and Russia to send Libyan mercenaries to fight alongside the Russian forces in Ukraine.