With the help of the local police, the Special Investigation Team from Patna took a person into custody at Bistupur in the steel city last night, they said.
He was being questioned in connection with the incident, the sources said.
The chief of the Ranvir Sena, private militia of upper caste landlords, was gunned down on June one at Khopira village in Bihar's Bhojpur district, triggering violence and arson.
Singh, alias Mukhiya ji, who faced several cases of carnage he had allegedly perpetrated on the lower caste landless poor, including in Laxmanpur Bathe where 61 Dalits were massacred in December 1996, was acquitted and released from jail in April this year.
