Bhubaneswar, Dec. 3: The Union home ministry today handed over the investigation into the fire incident in three express trains at Puri railway station on November 12 to the National Investigation Agency (NIA).

The decision has been taken after the state government made a recommendation to the Centre in this regard a week back.

Odisha police had arrested Ramachandran Subash, the prime accused in the incident.

Sources said the Union home ministry had found credible information regarding a terror module, which carried out combustible blasts in railway coaches in Odisha and other places leading to fire in some train compartments.

A five-member team of NIA has already interrogated the 27-year-old Subash, a native of Tamil Nadu. The government railway police (GRP) today took him on five-day remand for further interrogation.

While Subash had already been quizzed by railway protection force (RPF) teams from Bihar, Uttar Pradesh and Uttarakhand for similar incidents, a two-member GRP team from Bengal today questioned him to ascertain his links with a similar fire incident in Kharagpur on November 12.

The accused during interrogation had said that he was introduced to four to five suspicious-looking people, who spoke Bengali, after he was invited to Calcutta by his friend Uttam. "Besides, he has taken a few other names but could not give their details," said a GRP official. Subash also told the investigators that he was paid in lakhs to carry out the arson.

"He has been changing his statement frequently and we are not being able to ascertain whether he is lying or not," said a GRP official.

Fire had broken out in two bogies of the New Delhi-Puri Nandankanan Express, while two coaches of the Tirupati-Puri Express were gutted. Subsequently, fire had spread to a general compartment of the Puri-Howrah Express stationed at platform No. 6.