An army soldier was injured when Pakistani troops resorted to unprovoked firing along the Line of Control (LoC) in Jammu and Kashmir's Kupwara district, defence sources said Sunday.The Pakistan troops used mortars and machine guns to target Indian positions in Nowgam sector of the LoC in Kupwara Saturday, said the defence sources."Our troopers responded with same calibre weapons. It is likely that they resorted to unprovoked firing to push in terrorists. However, they did not succeed because of the alertness of our troopers," the sources said.