New Delhi  - A suspected Sikh militant opened fire in a railway station in India's northern state of Punjab on Tuesday, killing a vendor and injuring two policemen, news reports said.

Police said the man started shooting at policemen in the state's industrial hub of Ludhiana in the early hours of Tuesday, after they tried to check his bag, the PTI news agency reported.

The man was identified as Balbir Singh Bhootna who got off the Jhelum Express.

"Bhootna was arrested after an exchange of fire which lasted one hour," district police officer Sukhchain Singh told the PTI. A woman who was accompanying the suspected militant was taken into custody.

A vendor was killed during the shootout. Two police constables wounded in the shooting were being treated at a local hospital in Ludhiana, 100 kilometres west of state capital Chandigarh.

"We suspect that he might have links with some terrorist outfit. Our interrogation is on and very soon we will reach some conclusion," another police officer SS Kalia told the IANS news agency.

Local news channels said several cases including under the Terrorist and Disruptive Activities Act and Explosives Act were registered against him in Punjab.

A secessionist militant movement led to the deaths of hundreds of innocent civilians, security personnel and insurgents in Punjab state, home to a majority of Sikhs, in the 1980s.

The movement died out in the early 1990s following strong police action and a gradual fall in public support.

Although Sikh militancy has largely been eliminated from Punjab, Indian police say some "remnants" of the militancy still exist in India and abroad.

According to Indian officials, Sikh extremists based in Britain, Germany, Canada and Pakistan are trying to revive the militant movement. (dpa)