Pakistan summoned the Indian ambassador Thursday after a "spy drone" was shot down in disputed Kashmir, as officials said five people were killed in cross-border shelling between the two nuclear-armed neighbours.

The flare-up between the two countries, who have fought three wars since 1947, comes days after their prime ministers met in Russia in an apparent sign of a thaw in relations.

The Pakistani military said Wednesday that troops had shot down "an Indian spy drone used for aerial photography" close to the de facto border in Kashmir.

A picture in Pakistani media purportedly of the downed drone showed a small lightweight model of a type widely available for commercial purchase.

Following the incident, Pakistan's foreign ministry hauled in the Indian high commissioner, or ambassador, to hear a "strong protest over airspace violation", a statement said.

The ministry said the intrusion of the drone, which came down in the Pakistan-administered part of Kashmir, was a violation of international law and territorial integrity.

"The photograph of the drone in question indicates that it is not of Indian design nor of any UAV category held in the inventory of the Indian armed forces," S Jaishankar, Foreign Secretary told reporters in New Delhi on Thursday.

Refuting Pakistani charges, the foreign secretary put the onus of peace at the border, on Pakistan.

India was committed to steps that "contribute to ensuring peace and tranquility," he said.

"However there should be no doubt that any unprovoked firing from (the) Pakistani side would meet with an effective and forceful response...we will not let down our guard against infiltration and cross border terrorism," Jaishankar added.

Pakistan also protested to the envoy over what it called "unprovoked ceasefire violations" along the disputed border.

The two countries both control part of Kashmir, but claim the territory in full and have fought two wars over the Himalayan region.

They agreed on a border ceasefire in 2003, which has largely held, though violations are regularly reported from both sides.

Pakistani officials said Indian fire on Wednesday and Thursday had killed at least four civilians, including one in Kashmir and three near the town of Sialkot, which lies close to the border.

For its part, India protested to Pakistan over the firing, a government source said.

The complaint was registered after India claimed one of its civilians was killed in fire near the undisputed part of the de facto border in Jammu's Akhnoor sector on Wednesday, the source told AFP.

"Our high commission in Pakistan has lodged a protest. This matter was also taken up with Pakistan High Commissioner Abdul Basit in New Delhi," the source said.

India said the latest flare up had killed a 42-year-old woman and injured six others, including three border police.

Television footage showed Indian villagers holding empty mortar shells and cartridges, which they alleged had been fired by Pakistani rangers.

Last Friday, Indian Prime Minister Narendra Modi accepted an invitation from his counterpart Nawaz Sharif to visit Pakistan next year, raising hopes of an improvement in perennially difficult relations.

After months of stalemate and recriminations, Modi and Sharif spoke for about an hour while visiting Russia for a regional summit.

It will be the first time that Modi -- who has a reputation as a hardline nationalist -- has travelled to Pakistan since coming to power.