Calcutta, Jan. 23 :     A local CPM leader's murder this morning triggered large scale violence in parts of South Calcutta with CPM cadre setting fire to the Kasba market, ransacking a police station and damaging vehicles on Bijon Setu. Gurupada Bagchi, 51, secretary of the CPM's Kasba (south) local committee, was shot through the head by an unidentified killer while shopping in the Kasba fish market around 7.20 am. The CPM leadership charged the local police with bias and alleged that the killing was masterminded by thugs backed by the Trinamul Congress. The inspector-general of police (South Bengal), K.J. Singh, is now camping in the Kasba police station. No arrest has been made so far. Within minutes of the murder, a mob of CPM activists ransacked the police station and set fire to the Kasba market. Nearly 350 shops were gutted. Eight constables were injured and six cars were damaged. At least five scooters and important files from the police station were thrown into a nearby pond. The CPM has called a 24-hour bandh in the area on Monday in protest against the killing. Rioting cadre blocked traffic on the Rashbehari Avenue-Bypass connector till around 5 pm. Suburban railway services were also disrupted in the Sealdah South section in the morning. CPM MLA from Ballygunge Rabin Deb alleged that a Trinamul Congress-backed criminal, Tarak Halder, was the kingpin of the murder conspiracy. But Halder's name did not figure in the FIR which local CPM councillor Keya Dasgupta lodged with the police eight hours after the murder. Gurupada Bagchi, an upper division clerk in the West Bengal Higher Secondary Council, was secretary of the CPM's Kasba (South) local committee. He was assigned to oversee the party's education cell in south Calcutta. Even last night he attended a meeting to decide on funds for a new building of Charu Chandra Evening College in the locality. He was supposed to finalise the papers in another meeting this morning. The Kasba police station is just about half a kilometre from where Bagchi was killed but the police reached the spot after nearly an hour. The CPM's Kasba Bazar Committee secretary, Ujjal Joardar, and two others took the bleeding Bagchi to SSKM Hospital where he was declared dead. As soon as news of Bagchi's death reached Kasba, a 1,000-strong mob stormed the police station. It attacked the adjacent barracks, damaging furniture, utensils and valuables. Some arsonists tried to set fire to the barracks by pouring petrol on the debris. 'The situation came to such a pass that we had to take refuge in an upstairs room. No senior officer was in the police station,' said a constable, Nityananda Sarkar who was heckled by the mob.