Thirteen paramilitary soldiers were dead after clashes erupted overnight with forces on the Afghan side of the border, security officials said on Wednesday. A dispute arose after Afghan troops tried to set up a checkpost in a disputed part of Mohmand Agency, one of country's troubled tribal areas bordering Afghanistan. "Overnight some shells landed in the Pakistani area and hit paramilitary positions. We have reports of some casualties on our side because of the firing from across the border," a local official told Agencies. "It's very remote and mountainous terrain and we are checking the number of casualties," the official said, adding that the incident happened in the Soran Dara area, bordering the Afghan province of Nangarhar. Pakistani and Afghan military spokesmen were not immediately available for comment.