Chief of the Security Service of Ukraine (SBU) Valentyn Nalyvaichenko has said that there is every reason to believe that a group of employees of the Russian Federal Security Service (FSB) participated in planning and implementing measures on the so-called anti-terrorist operation in Kyiv during mass protests in February 2014.

"We have reasonable grounds to believe that these groups, who were on one of the SBU firing grounds, participated in planning and implementing measures on the so-called anti-terrorist operation," he said at a briefing in Kyiv on Thursday.

"An answer from the Investigative Committee of the Russian Federation is very important to us. We are interested in two questions. The first - December 20, 2013: at an SBU firing range, there were 26 employees of the FSB of the Russian Federation. Let them give us an answer to what they did, their ranks and posts. In mid January 2014 – there were six employees, citizens of the Russian Federation – what did they do, what tasks did they have, and what did they plan?" Nalyvaichenko said.