NEW DELHI — Indian officials are advising residents of strife-torn Kashmir to prepare for a possible nuclear war by building bombproof basements and stockpiling food and water, adding to tensions between India and Pakistan, both nuclear powers, after deadly cross-border skirmishes in recent weeks.

“People should construct basements where the whole family can stay for a fortnight,” read the advisory, which was published Monday in the newspaper Greater Kashmir. It comes in the midst of the worst fighting in Kashmir between India and Pakistan since a cease-fire was signed in 2003. Three Pakistani and two Indian soldiers have been killed, and one of the Indian soldiers was found without his head.

News of the mutilation infuriated Indians, with Sushma Swaraj, the leader of the opposition in the lower house of Parliament, calling for India “to get at least 10 heads from their side” if the Pakistanis did not return the soldier’s head. After criticism that he was not doing enough, Prime Minister Manmohan Singh of India said he was reviewing ties with Pakistan. A special visa program between the two countries has been suspended, and Pakistani players in a new Indian field hockey league have been sent home.

Officials insisted that the advisory published Monday was unrelated to these developments. Yoginder Kaul, the inspector general of the Civil Defense and State Disaster Response Force, said the advisory was meant to commemorate the first anniversary of the creation of his unit.