The Central Bureau of Investigation sleuths probing the Birbhum carnage on Sunday interrogated arrested local Trinamool Congress leader Anarul Hossain and other accused persons, besides recording the statement of those who were injured in the violence.
Experts of the Central Forensic Science Laboratory, Delhi, who arrived Rampurhat on Friday, collected samples from the place of occurrence in Bogtui village, which is almost deserted following the gruesome incident on the night of March 21.
CBI officers also visited the village near Rampurhat, where eight people were charred to death after their houses were set on fire, in a suspected fallout of a local TMC panchayat leader's murder.
A team of CRPF personnel are providing security to the sleuths of the central agency, who are investigating the case on a Calcutta High Court order.
Earlier, a state government formed SIT was conducting an enquiry.
Anarul Hossain, who was arrested by the police within hours of a directive by Chief Minister Mamata Banerjee on Thursday to hunt down all accused including her party workers and leaders, was taken to the CBI camp office from Rampurhat police station in the morning and was interrogated by the agency's officers.
Hossain, a former TMC president of Rampurhat block-I, was questioned along with two others accused, a CBI officer said.
The Calcutta High Court had directed the state police to hand over custody of all arrested persons in connection with the case to the CBI.
Another team of CBI officials visited the Rampurhat hospital on Sunday and recorded the statement of the four injured persons.
"They spoke to the patients; I was there," superintendent of the government hospital, Dr Palash Das, told reporters.
The sleuths could not question a woman, who has suffered over 60 per cent burns, as her condition is still not okay to take questions.
The CBI team, led by a DIG-rank officer, reached Bogtui on Saturday morning following the high court order and took charge of the investigation.
"We will also interact with local people in Bogtui village. We have requested the administration to trace those who fled the village. The Central Forensic Science Laboratory personnel will continue their examinations," a CBI official told PTI earlier in the day.
The sleuths of the central agency will also interact with fire brigade officials to understand what had transpired on that dreadful night, he said.
A number of villagers who lost their family members left Bogtui following the incident and are staying at Bataspur, around 40 kilometres from their village.
The high court has directed the CBI to submit a progress report before it by April 7.
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