India and Pakistan on Tuesday tallied at least 13 deaths in recent firing across their disputed border in Kashmir, where the nuclear-armed neighbours are ratcheting up shelling and small-arms fire.

Tension over the Himalayan region has run high since a September cross-border raid on an army base killed 19 Indian soldiers, prompting what New Delhi called retaliatory ‘surgical strikes’ against Islamist militants in Pakistan.

Each accuses the other of repeatedly violating a 2003 ceasefire. On the diplomatic front, already chilly relations have gone into the deep freeze following recent tit-for-tat expulsions of diplomats.

Both sides dispute each other's version of events, against the backdrop of heightened tension in Indian-ruled Kashmir after security forces killed a separatist field commander in July.

Pakistan officials said at least four people were killed and five injured in its part of Kashmir on Monday, as the archrivals exchanged heavy fire concentrated in Pakistan's Nakyal sector along the Line of Control.

‘It appears as if a full blown war is going on between India and Pakistan,’ said Mohammad Saeed, a resident of the village of Mohra in the region.

‘Please have mercy and stop it,’ he said, speaking to Reuters by telephone amid the sound of gunshots.

Six people were killed and 10 injured in Nakyal and the adjacent Tatta Pani sector last Friday and Saturday, Pakistan has said.

On the Indian side of the Line of Control, a girl died and three people were injured on Tuesday, in Pakistani shelling along the Ramgarh sector in Jammu and Kashmir, a senior police officer told Reuters.

On Monday, an Indian soldier and a civilian were killed along the line of control in Kashmir in the Rajouri sector on the Line of Control, an Indian army spokesman said.

The increasing cross-border firing is raising fears that military escalation could trigger a potentially devastating nuclear exchange over Kashmir, the bone of contention that has sparked two of the three wars between India and Pakistan since partition and independence from Britain in 1947.