Police have detained 20 of the alleged attackers.
Social activist Swami Agnivesh was attacked and beaten up, allegedly by supporters of the Bharatiya Janata Party Yuva Morcha (BJYM) in Jharkhand''s Pakur district on Tuesday.
Police said the 80-year-old was attacked when he was going to participate in the 195th Damin Mahotsav at Littpara. The incident occurred just when he stepped out of his hotel.
The attackers first shouted slogans and showed black flags and later thrashed him even as he fell on the ground and his aides did their best to protect him.
The police detained 20 of the attackers.