Jammu, Oct 4 Indian and Pakistani troops on Thursday exchanged heavy fire along the Line of Control (LoC) in Jammu & Kashmir's Poonch district. One Pakistani ranger was killed in the firing.Defence sources said Pakistan army resorted to unprovoked shelling and firing on Indian positions, including civilian facilities, in the Gulpur sector of the LoC, the de factor border between the two countries. "Pakistani troops are using automatics, small arms and mortars. Our positions are strongly and effectively retaliating," a source said."Heavy exchange of fire is going on in the area", the source added.