A 30-member team of the Central Bureau of Investigation (CBI) has reached Rampurhat in West Bengal's Birbhum district and started a probe into the violence that claimed eight lives earlier this week.

Unidentified people had on March 21 set ablaze 10 houses in Bogtui village near Rampurhat town, killing at least eight people, including women and children. The CBI team, that reached Rampurhat late on Friday night, started the probe early on Saturday morning under the leadership of a DIG-rank officer.

"We have started the investigation today. We have to conduct the probe on a war-footing as we have a deadline to meet," a CBI official told PTI. Dividing themselves into three groups, one CBI team headed by DIG Akhilesh Singh visited Purbapara locality in the village where the carnage took place early on Tuesday after the murder of local TMC leader Bhadu Sheikh on Monday evening.

They spent nearly five hours in Bogtui, where they first went to the house of Sonu Sheikh, from where seven charred bodies were found. CBI sleuths examined Sonu Sheikh's residence and the burnt remains in it, and then proceeded to the neighbouring houses including those of Fatik Sheikh and Mihilal Sheikh.

Besides conducting videography, the CBI sleuths, along with Central Forensic Science Laboratory (CSFL) personnel, carried out 3D scanning of the area and collected samples from the spot. "It was also investigated whether the fire was set by people from outside the houses, or if there were some other reasons behind the incident," another official said.

He said there are plans to speak with witnesses of the incident, and a detailed list of all inhabitants of the area is being prepared. "Speaking to witnesses and other villagers is required. We are preparing a list of the local inhabitants," he said, adding that the CBI sleuths will stay in Birbhum district for the probe.

Another CBI team went to Rampurhat police station and studied the case diary and other related documents in connection with their probe. CBI officials also held a meeting with IG (Bardhaman range) B L Meena and Birbhum district Superintendent of Police Nagendra Tripathi on Saturday.

The Calcutta High Court on Friday handed over the investigation into the Birbhum killings to the CBI and set a deadline of April 7 to submit its progress report.