A man who attempted to rob a bank in central Prague on Wednesday left behind explosives before fleeing the scene, the police said. The suspect entered the CSOB bank's branch in Prague's Wenceslas Square around 1PM; he asked a teller for a large sum of cash and threatened her with a bomb. However, he left the premises when told such amount was not available, leaving his suitace in the bank. The police said on Wednesday night a functional explosive device had been discovered inside; some media reported a four-kilo explosive charge was found. Parts of the area were closed off before the bomb was taken away while the police are searching for the suspect.