The FIR was been registered on the complaint of Upendra Manjhi, nephew of Chief Minister Jitan Ram Manjhi, station house officer of Khijarsarai police station Sushil Kumar Rahul said.
The FIR has been lodged under IPC section 506 (punishment for criminal intimidation) and SC/ST Act, he said.
The complainant said that during a television interview on February 11, Singh, known for using muscle power in politics, used filthy language and threatened to beat up the Chief Minister, and considering his background, the family felt threatened.
Gaya is the home district of Manjhi.
