Afghan authorities say insurgents have poisoned the food of policemen and then attacked their checkpoint in southern Afghanistan, leaving six people dead. The Helmand province governor's office said Tuesday that militants poisoned the food at the police outpost in Nahri Sarraj district and then started a gun battle Monday night with police there. Four policemen were killed and two were wounded in the fighting. The bodies of two civilians also were found at the checkpoint, according to a report of the Associated Press. Taliban spokesman Qari Yousef Ahmadi claimed responsibility, saying the insurgents poisoned the police and took their weapons. A government delegation has been sent to the area to investigate.