A key witness in the Samjhauta Express blasts has failed to identify a suspect as the person who got off the train minutes before the explosions and was believed to be behind the attack that killed 68 people.

Haryana police paraded the suspect before the injured Mohammed Shaukat Rana, a Pakistani national who has claimed to have seen two of the possible bombers, at Safdarjung hospital where he was admitted on Tuesday, his cousin Jamat Ali said.

He claimed that Rana did not identify the suspect as the person who got off the compartment 15 minutes before the blasts and was believed to be behind the explosions that ripped apart the train around Sunday midnight.

Rana had earlier said that he saw two persons alighting from the train after one of them had a fight with Railway Police personnel on the night of incident.

Haryana police had on Tuesday released sketches of two persons prepared on the basis of the description provided by eyewitnesses.

Police described one of the two suspects as a plump man in his mid-30s with a wheatish complexion and sporting a moustache. The other person was around 27 years and had his face covered with a muffler.

The police had also announced a reward of Rs 1 lakh to anyone providing credible information about the suspects.

Another Pakistani national Usman Mohammed has also told a magistrate in Panipat that he saw four people getting off the train before the blasts.

Rana, who survived the blasts with serious injuries along with his wife Ruksana and one-year-old daughter Aksa, lost four of his children in the attack. The fate of the couple's another child is still not known.