Indian National Lok Dal (INLD) leader Subhash Nishad was produced before the district courts and remanded to one-day police custody on Thursday.
He was arrested in a case of rioting and voluntarily causing hurt on Wednesday.
Former councillor Nishad, a resident of Abheypur village, lost the municipal corporation (MC) elections from Ward No 13 to Ravi Kant Swami of the Bharatiya Janta Party (BJP) by 139 votes.
On Wednesday morning, he allegedly, along with his supporters, had attacked Rinku of Abheypur village as he was supporting Independent candidate Rajesh Kumar who secured 555 votes in the polls. He allegedly blamed Rinku for his defeat.
In the attack, Rinku and his mother Munni Devi were injured.
The police registered a case under sections 148 (for rioting), 149 (for being a member of unlawful assembly) and 323 (for voluntarily causing hurt) of the Indian Penal Code (IPC) against Nishad and six others.
Stones pelted on leader's car
Around 1 am on Thursday, some unidentified persons pelted Nishad's Scorpio car with stones and damaged it. The windowpanes of the car were broken in the incident.