An Indian paramilitary trooper stands guard near a barbed wire barricade during curfew-like restrictions in downtown area of Srinagar in Indian-controlled Kashmir. Picture: Xinhua/Javed Dar

New Delhi - Six Hindu pilgrims were killed after militants opened fire on a bus in India's Muslim-majority Jammu and Kashmir state on Monday, officials said.

A group of militants opened fire on a bus travelling through the Anantnag district, some 50 kilometres south of Srinagar.

The pilgrims inside the bus were returning from the Amarnath cave shrine, dedicated to the god Shiva, located at a height of 3,888 metres in the Himalayas.

Six pilgrims were killed and 12 more were injured in the attack, the state's senior police official Muneer Khan said.

This is the first time in nearly two decades that Amarnath cave pilgrims have come under attack. At least 32 pilgrims were killed in an attack in 2000.

Media reports said the bus was not part of the main pilgrimage convoy and apparently did not have any security cover. The buses travel in a convoy guarded by paramilitary forces.