Trinamool Congress Rampurhat-1 block president Anarul Hossain was arrested on Thursday in connection with the killings in Bogtui village in West Bengal's Birbhum district, police said.
He was arrested from Tarapith in the district within hours of Chief Minister Mamata Banerjee directing the police to nab him for not paying attention to local people's apprehension of possible disturbance in the area, which ultimately snowballed into the carnage, a senior officer said.
Searches were conducted in various parts of the district including Hossain's residence, after which he was nabbed from Tarapith. Hossain was picked up from near a hotel after police tracked his mobile phone tower location, he said.
The local TMC leader will be questioned over the incident in which eight people were burnt alive on Tuesday, he added.
Meanwhile, the Rampurhat police station inspector-in-charge Tridib Pramanik was suspended for negligence.
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