The police officer, who asked not to be named, said three or four militants had launched the attack. At least two junior commissioned officers were killed, the officer said, and two women and two children - relatives of army personnel - were among seven injured in the fighting.

SD Singh Jamwal, the inspector general of police in Jammu, said that at about 4:55 am, a guard noticed suspicious movement before gunfire on his bunker.

As of noon, fighting was still ongoing, said Jamwal. The site was cordoned off and surrounded by police and army units called in as reinforcements.

"The fire was retaliated. The number of militants isn't known," he said. "They've been cornered in one of the family quarters."

India accuses Pakistan of training and arming militants and helping them infiltrate across the Line of Control that divides the Kashmir region. Pakistan denies the allegations.

The South Asian neighbours have fought two of their three wars since independence in 1947 over Muslim-majority Kashmir, which they both claim in full but rule in part.