OSCE SMM Principal Deputy Chief Monitor Alexander Hug stated this at a briefing in Lviv on Tuesday, an Ukrinform correspondent reports.
"We report what we see. And we have seen insignia of the Russian Federation and other nations. We have spoken to people who claimed they had been part of army of the Russian Federation," Hug said.
He also noted that observers had seen specific types of weapons and had described in their public reports, including electronic warfare equipment.