The agency officials have stepped up work for the past couple of days, even visiting the accident site. A team is on the lookout for prime accused Bapi Mahato and Umakanto Mahato. According sources in Delhi, the focus of investigation will be the Maoists and the PCAPA, though all other angles will be looked into as well.

A special team headed by a DIG-rank officer is scheduled to land anytime in Kolkata. The agency would then lodge a formal FIR, either in a Jhargram court or with the SCB Kolkata and initiate investigation. The team will include forensics experts and is expected to visit the site in Jhargram next week.

It was Union railway minister Mamata Banerjee who demanded a CBI probe after visiting the tragedy site. Despite the state government’s reluctance, the Union home ministry granted the probe of the train tragedy to CBI.

The CID, which is currently probing the incident, meanwhile, claimed to have received vital leads after questioning Khagen Mahato, the first man arrested in the case.

Mahato owned the pick up van used to carry the PCAPA men to the site. The pick-up van was also recovered.