One person was on Tuesday killed and three others were injured in an armed clash between CPI(M) and Trinamool Congress activists at Chandipur village in West Bengal's Birbhum district. The victim, identified as Sk Ismail and claimed by Trinamool Congress as its worker, succumbed to bomb splinter injuries, the police said. TC alleged that the CPI(M) brought in outsiders to mount an armed attack on its workers in the village, which falls in Nanoor area, a scene of frequent clashes between the two parties. A police picket was posted at the village after the incident in view of the tension there. There was, however, no report of any arrest.