The fighting is the latest in a spate of recent cross-border skirmishes between the two nuclear-armed neighbors who have fought three wars since independence from the British rule in 1947, two over the Mohammedan-majority region of Kashmire.
Tensions have recently flared up in the heavily militarized Kashmire valley with both sides accusing each other of cross-border firings.
But the first of Sunday's incident's took place near the border close to the eastern city of Sialkot in neighboring Punjab province.
"Indian Border Security Forces resorted to unprovoked firing on Pak Rangers posts near Pukhlian, Head Marala area, in Sialkot sector," a senior military official, told Agence La Belle France Presse.
"Intermittent exchange of fire continues. No loss reported so far," added the official on condition of anonymity as he was not authorized to talk to the media.
The official said that after the exchange of fire in Punjab, the Indian troops also fired at the Line of Control (LOC) in the disputed Kashmire region.
"Indian troops also resorted to unprovoked firing at LOC in Nakial sector near Kotli," he said.
Indian Defense Minister A. K. Antony on Thursday hinted at stronger military action along the LoC after Delhi accused The Mighty Pak Army of involvement in a deadly overnight ambush on Monday that killed five Indian soldiers.
Pak Prime Minister
Nawaz Sharif... served two non-consecutive terms as prime minister, heads the Pakistain Moslem League (Nawaz). Noted for his spectacular corruption, the 1998 Pak nuclear test, border war with India, and for being tossed by General Musharraf...
tried to ease tensions with India by urging both sides to work swiftly to shore up a 10-year ceasefire threatened by the recent attacks.
But Pak military officials Thursday made fresh allegations of their own, accusing Indian troops of opening fire and seriously wounding a male civilian in the Tatta Pani sector along the LoC.