The death toll in the train derailment in Andhra Pradesh's Vizianagaram district rose to 41 as NIA and CID teams visited the scene on Monday to study if there was sabotage.
Two more bodies were recovered from one of the derailed coaches of the Jagdalpur-Bhubaneswar Hirakhand Express on Monday, police said.
The tragedy occurred on Saturday at 11.30 pm near Kuneru station, 24 km from Rayagada in Odisha. The train was on its way to the Odisha capital Bhubaneswar from Jagdalpur in Chhattisgarh.
Officials said 68 passengers were injured due to the derailment of nine coaches. They were being treated in hospitals in Andhra Pradesh and Odisha.
A National Investigation Agency (NIA) team visited the accident site on Monday to probe the sabotage angle.
NIA is already probing the alleged role of Pakistan's Inter Services Agency (ISI) behind the Indore-Patna Express derailment near Kanpur in Uttar Pradesh that claimed 150 lives.
Andhra Pradesh's Crime Investigation Department (CID) also visited the accident site on Monday.
The CID officials included Additional Director General of Police Dwaraka Tirumala Rao and Inspector General of Police Amit Garg.
Officials have not ruled out the involvement of Maoists as the Andhra-Odisha border area is considered a Maoist stronghold.