The firing took place when the two GRP constables of the Narcotics cell tried to check the bag of the suspected terrorist in Jammu-bound Jhelum Express which arrived in Ludhiana from Pune around 3.30 am at platform No 4 of the railway station, they said.
The suspected terrorist identified as Balbir Singh Bhootna immediately got down and hid himself under a compartment of the Jhelum Express and opened fire at the police, which retaliated on the platform near the compartment.
"Bhootna was arrested after an exchange of fire which lasted around one hour," Ludhiana Senior Superintendent of Police Sukhchain Singh told PTI.
A woman, who was accompanying the suspected terrorist, has also been taken into custody, Singh said. The vendor was killed on the spot during the exchange of fire, GRP Superintendent of Police S J P Sharma said.
The two injured head constables have been identified as Karanpal Singh and Naranjan Singh, he added.
It was believed that the suspected terrorist and the woman had arrived in the Jhelum Express from Nanded after boarding the train at Manmad in Maharashtra.
Additional Director General of Police Railway Chander Shekhar told PTI on phone that Bhootna was a resident of Mauli Wala village in Ferozepur district. Bhootna had fired from a .9mm pistol which has been taken by the police in its custody, the ADGP said without giving details of his group affiliation saying it would hamper the investigations.
The police was also trying to ascertain the identity of the lady accompanying him and her relationship with Bhootna, he added. Bhootna had been declared a Proclaimed Offender after in a case of recovery of arms and ammunition in Jalandhar district about three years back, police said.