In West Bengal, three persons, including a couple were shot dead by a state armed police constable at Barrackpore in North 24-Parganas district. The incident took place yesterday. The police said the Constable attached to the 8th battalion of state armed police, used his service revolver and bullets which he had allegedly taken from Latbagan barracks where he was posted . The firing is suspected to have been the outcome of some differences in the relations between the couple and the constable.