Pakistan has accused Indian forces of firing on its border posts close to eastern city of Sialkot in Punjab province, prompting an "intermittent exchange of fire" between the two sides.
The fighting is the latest in a spate of recent cross-border skirmishes between the two neighbours who have fought three wars since independence from British rule in 1947, two over the region of Kashmir.
Tensions have recently escalated in the heavily-militarised Kashmir valley, with both sides accusing each other of cross-border shootings but Sunday's incident happened in a different area, near the border.
"Indian Border Security Forces resorted to unprovoked firing on Pakistani rangers posts near Pukhlian, Head Marala area, in Sialkot sector," a senior military official told the AFP news agency.
"Intermittent exchange of fire continues. No loss reported so far."
AK Antony, Indian defence minister, hinted on Thursday at stronger military action along the de-facto border between the two countries in Kashmir - known as the Line of Control (LoC) - after India accused Pakistan's army of involvement in an overnight ambush on Monday that killed five Indian soldiers.
Nawaz Sharif, Pakistani prime minister, tried to ease tensions by urging both sides to work swiftly to reinforce a 10-year ceasefire threatened by the recent attacks.
But in a fresh allegation of their own on Thursday, Pakistani military officials accused Indian troops of opening fire and seriously wounding a male civilian in the Tatta Pani sector along the LoC.
The picturesque Himalayan territory of Kashmir is divided between India and Pakistan by the UN-monitored LoC but is claimed in full by both countries.
More than a dozen armed rebel groups have been fighting Indian forces since 1989, demanding independence for Kashmir or its merger with Pakistan.