Ukraine's SBU State Security Service has said it has collected an enormous amount of evidence proving the participation of Russia's regular military forces in battles against Ukrainian forces in Donbas, the SBU's press service has said.

"This is not just evidence of hybrid aggression in Russia, but also becomes powerful evidence for judicial decisions in favor of families affected by actions of the Kremlin," the SBU said on Facebook on Thursday evening.

SBU chief Vasyl Hrytsak also published materials proving a military presence and crimes on the territory of Ukraine by Russia's Wagner Private Military Company (PMC). He said Wagner PMC is suspected of downing an IL-76 Ukrainian military aircraft.

"Yesterday, a panel of judges of the Zaporizhia Court of Appeal recognized the death of Il-76 crew commander Oleksandr Bely on June 14, 2014 over Luhansk as a consequence of the Russian armed aggression against Ukraine. This ruling allows families of Ukrainian soldiers, who died defending Ukraine from the aggressor, to rely on social protection and international humanitarian help," the SBU said.