The Calcutta High Court on Friday ordered a CBI investigation into Birbhum violence that claimed eight lives earlier this week.
The court directed an SIT formed by the West Bengal government to hand over case papers and accused persons arrested by it to the central probe agency.
A division bench comprising Chief Justice Prakash Shrivastava and Justice R Bharadwaj directed the Central Bureau of Investigation (CBI) to file a progress report by April 7, the next date of hearing of the matter.
The bench said that the CBI probe was being ordered in the interest of justice.
Eight people, including two children, were charred to death in Bogtui village of Bengal's Birbhum district in the suspected fallout of a TMC panachayat official's murder.
The bench had suo motu taken up the case of the gruesome incident.
A set of PILs seeking CBI or NIA probe into the incident were also taken up for hearing by the court along with the suo motu petition.
The state police on Thursday arrested local Trinamool Congress boss Anarul Hossain from near a hotel in the pilgrimage town of Tarapith.
Earlier in the day, on visiting Bogtui village, the scene of Tuesday's fire bombing and burning of eight people, Banerjee vowed that the police would ensure the strictest punishment for the guilty and none would be spared.
She also indicated a larger clean-up of her administration by ordering a "dragnet to unearth secret caches of illicit arms and bombs" across the state.
"Police will ensure strictest punishment is handed out to culprits responsible for the Rampurhat carnage. The case filed before the court should be water-tight," she said.
The orders follow the murder of TMC panchayat leader Bhadu Sheikh at a crossroad near the village of Bogtui, on the outskirts of Rampurhat town in Birbhum district of Bengal.
In an apparent revenge attack, petrol bombs were hurled at 10 houses in the village and 8 people including women and children killed by burning within hours.
The attacks and counter-attacks are widely believed by locals to be the result of rivalry over illicit sand mining, though the police is still investigating the cause and sequence of events.
The chief minister met family members of the victims and offered them permanent government jobs and compensation to rebuild their houses.
She also visited the house of Sheikh, and gave the same offers to his next of kin.
Banerjee announced a compensation of Rs 5 lakh each to the next of the kin of the victims, and Rs 2 lakh each for rebuilding the damaged houses.
Those injured will be provided with Rs 50,000 each.
Security in Bogtui village was also beefed up on Thursday evening following Banerjee's directive.
Over 50 policemen were posted in Bogtui village while CCTVs are also being installed to increase security for the villagers there who have complained they lived in ear, a senior officer of district police said.
Around 69 people of five families had fled to neighbouring villages following the series of attacks and counter-attacks, another police officer said.
A fact-finding team sent by BJP from Delhi and Leader of the Opposition in Lok Sabha, Congress leader Adhir Ranjan Chowdhury also visited Bogtui village.
Both had been stopped en-route earlier by the police as the chief minister was visiting the spot but were later allowed to proceed.
The BJP team, which included former Uttar Pradesh DGP Brij Lal, Mumbai ex-police commissioner Satya Pal Singh and Bengal BJP chief Sukanta Majumdar, also assured help to the families of those killed in the violence.
"We have come here to witness the situation in the aftermath of the mass murder. This (TMC) government has lost its moral right to govern. What happened in Bogtui is a shame for humanity," Majumdar told reporters after visiting the village.
"The chief minister had been claiming that all culprits will be punished. The police, on the other hand, are trying to hush-up the matter," he alleged.
Meanwhile the Calcutta High court which met on Thursday reserved its order on a suo motu petition on the mass murder, along with a bunch of PILs seeking a probe by CBI or NIA into the killings.
The state opposed the plea for a probe by central agencies pointing out that an enquiry is being conducted by a Special Investigation Team formed by the West Bengal government and prayed that it be given time to complete the probe.
The court had also ordered a forensic probe by the Central Forensic Science Laboratory (CFSL), Delhi on Wednesday.
Additional Solicitor General Y J Dastur who submitted that the CBI or the NIA are ready to initiate a probe if an order is passed by the high court to that effect, also informed that a seven-member team from CFSL will proceed to Bogtui after reaching Kolkata on Thursday evening to collect samples from the crime scene.
(With PTI Inputs)