The shelling along with firing exchanges started late Wednesday night, police said.
"After Pakistan Rangers used 82 mm mortar shells to target civil and Border Security Force (BSF) facilities in R.S.Pura, the BSF retaliated effectively using same calibre weapons," police sources said.
"Shelling and firing exchanges took place in Korotana Kurd, Bidipur, Jattan, Abdullian, Chandu Chak, Shamka and Hansu Chak areas."
Loud explosions could still be heard in these areas.
No reports of human casualty or damage to property have so far been reported, the sources added. But six people were injured during the same.