sentences:  Because of all the conflict, the UGT and CNT agreed with the Generalitat to cancel any celebrations on May Day.On 3 May, Assault Guards of the government attempted to take over the CNT-controlled telephone exchange building in Barcelona, but were held off by gunfire.The assault guard laid siege to the building, and fighting between the anarchists and POUM on one side, and Communists and the government forces on the other began.