KIEV, February 20. /ITAR-TASS/. A poisonous agent has been used against the police in Kiev, an official has said.

“There has been evidence of some poisonous agent having been used against police. Measures are being taken to find out what the substance was,” Interior Ministry spokesman Sergei Burlakov said.

Earlier Ukraine's Interior Ministry reported, that rioters on Independance square in Kiev openely fired shotguns against Berkut riot police units injuring at least 20 policemen.

Shots were being fired at police from the windows of the conservatory building overlooking Independence Square.