Four security personnel and two suspected Islamic militants have died in a battle at a crowded railway station in Indian-administered Kashmir.
Police take cover at the station in Jammu
More than 20 people were hurt in the exchange of fire at Jammu station.
The battle erupted after security personnel challenged the two men, who were dressed as policemen.
The attack comes a day before Indian Prime Minister Atal Behari Vajpayee is due to make his first visit to Pakistan in four years, for a regional summit.
Police said the dead included two Border Security Force personnel, one policeman and a soldier.
The injured were mostly security personnel but also included a two-year-old child.
According to witnesses, two armed militants wearing black leather jackets and khaki trousers entered the station through the main gate at around 6.30pm (1300 GMT).
Anil Kumar, one of the injured Border Security Force personnel, who was waiting to board a train, said police on guard duty became suspicious and started following them.
The militants saw the police and crossed the bridge connecting the two platforms.
"They first hurled grenades and then fired indiscriminately from the bridge," said Mr Kumar.
The firing caused panic and police evacuated passengers from the area.
Soldiers and armoured vehicles quickly cordoned off a one-square-kilometre area around the station.
The exchange of fire continued intermittently for about two hours with the army firing rocket launchers and automatic weapons.
The director-general of Jammu and Kashmir police, Gopal Sharma, arrived at the station to supervise operations.
Troops were ferried in bullet-proof vehicles to the area where the militants were thought to be hiding.
The injured were taken to the main government hospitals in Jammu, where the condition of at least six was said to be critical.
Security in Jammu has been high following intelligence reports of possible terrorist strikes on the eve of the South Asian Association for Regional Co-operation summit in Islamabad.
The train station in Jammu, winter capital of the state of Jammu and Kashmir, was the scene of a previous attack in August 2001 which left 11 people dead.
Kashmiri militant groups are fighting for independence from India, which controls about 45% of the region.
India accuses Pakistan of sponsoring militant attacks in Kashmir, but Pakistan says it provides only moral and diplomatic support.
The territory has been at the centre of two wars between them since 1947.
However, ties between the two countries have improved in recent months.