"The situation is tense but under control, with no report of any fresh clash from anywhere so far," said Nawada District Magistrate Adesh Titarmare.
He said the government has invoked the National Security Act (NSA) for preventive detention and swift action against troublemakers.
Curfew was imposed in the town where police resorted to firing Monday following a violent clash between two communities. "Assembly of five or more people at any particular place and display of firearms have been banned," said Nawada Superintendent of Police M.S. Dhillon.
Dhillon said 15 people have been detained in connection with the violence.
Additional security forces have been deployed and patrolling intensified.
On Monday, at least half a dozen people were seriously injured in a clash between two communities. Police resorted to firing when a mob attacked the Bundelkhand police station in Nawada, about 150 km from here.
Communal tension erupted Friday when an altercation took place between a group of kanwarias (Hindu pilgrims) and another community at a roadside eatery in Nawada.
District officials said clashes continued after the death of a 20-year-old youth, Kundan Kumar, who was injured along with three others in police firing Saturday.
Kundan Kumar died at the Patna Medical College and Hospital Sunday. District authorities had imposed curfew in Nawada for a few hours Saturday but later lifted it.
Dhillon said Assistant Sub-Inspector Kamal Narain Singh of Nawada town police station has been suspended on charges of dereliction of duty.
Chief Minister Nitish Kumar expressed concern over the situation in Nawada, and directed officials to take stern action against anti-social elements. Nitish Kumar further appealed to people and all political parties to help the government ensure peace and social harmony in Nawada town.
"I will not allow any one to flare up communal tension in the state and government will take all steps for the restoration of peace and harmony," he said.