The incident was reported around 4:35 am (1105 GMT) at the Bathinda military station in Punjab, a northern state where tensions have been high over the local resurgence of a separatist movement.

"The area continues to be sealed off and joint investigations with Punjab Police are being coordinated to establish the facts of the case," the army statement said.

Bathinda's top police official G.S. Khurana told broadcaster NDTV that the incident did not appear to be a terror attack.

State police and India's defence ministry did not respond to AFP requests for comment.

Punjab has been on the edge since last month when authorities launched a manhunt for firebrand Sikh separatist preacher Amritpal Singh.

Singh has in recent months rallied a huge following by demanding the creation of Khalistan, a separate Sikh homeland, the struggle for which sparked deadly violence in Punjab in the 1980s and 1990s.

He remains at large after eluding despite a huge police dragnet involving thousands of police officers and a statewide internet shutdown that lasted for several days.