Five clashes — involving shelling and gunfire — were reported along the 740km-long unofficial border that has separated the nuclear-armed rivals for the past seven decades.

The new peak in tensions came only five days after three Indian troops and three militants were killed in an exchange along the so-called Line of Control (LoC).

After Friday’s battle, India’s military accused Pakistan of an “unprovoked” violation of a two-decades-old ceasefire that is habitually breached several times a week.

“Pakistan used mortars and other weapons” and “deliberately targeted civilian areas”, said an Indian army statement.

Three Indian soldiers were killed and three wounded in the Keran sector of the frontier. Kashmir police said three civilians were killed and at least three suffered serious injuries, with one man losing both legs.

Inhabitants of several villages were moved away because of the fighting.

Indian troops “retaliated strongly causing substantial damage to the Pakistan army’s infrastructure and casualties,” added the military statement.

Pakistani officials said there were casualties on its side of the LoC, but did not immediately give figures.

The two sides regularly stage artillery duels across the LoC, and invariably blame each other for the clashes.

Kashmir has been divided between the two countries since their angry separation in 1947. It has been a cause of two of their three wars since then.

Both countries claim the whole of the Himalayan region, where India is also fighting an insurgency that has left tens of thousands dead since 1989.