Kolkata, April 7 : Three members of a family were hacked to death at Sitalkuchi in West Bengal's Cooch Behar district on Friday. Those killed have been identified as Bimal Kumar Burman (68), his wife Nilima Burman (52) and their elder daughter Runa Burman (24). The couple's younger daughter Iti Burman (22) was also injured in the attack and is currently undergoing treatment at a local hospital, where her condition is stated to be critical. While Nilima Burman was an elected Gram Panchayat member for Trinamool Congress from Sitalkuchi, her husband was the Sitalkuchi block president of the Scheduled Caste/ Schedule Tribe/ Other Backward Class cell of the state's ruling party. Additional district police superintendent Amit Verma said that the prime accused Bibhuti Bhusan Roy and two of his associates have already been arrested from the crime spot. Further investigation is on, he added. Meanwhile, as per the locals, Bibhuti Bhusan Roy was in a relationship with Iti, which her family strongly disapproved of. This morning, on hearing screams, the neighbours rushed to the Burman's residence only to find the four family members lying on the grounds bleeding profusely and the three accused standing at the spot. The neighbours nabbed the three and handed them over to the police. Although there were frequent fights over the alleged affair, none could imagine that the matter would take such a tragic turn, the neighbours said. /IANS