Fifteen persons, including RJD youth wing workers, were arrested on Sunday over a clash between two factions of the JDU in front of chief minister Nitish Kumar's 1 Aney Marg residence on Saturday.

They have been booked for trespassing, wrongful confinement, assault and under sections of the Motor Vehicles Act.

Patna senior superintendent of police (SSP) Manu Maharaaj said on Sunday that the arrests were made on the basis of CCTV camera footage. The police team headed by city superintendent of police (central) D. Amarkesh arrested 15 suspects, including Vinod Yadav and Rahul Kumar, who had allegedly organised the supporters of rebel JDU leader Sharad Yadav. The duo had allegedly provided Rs 100 each to the youths for taking part in the protest in the prohibited zone.

The SSP said raids were on to nab 15 others whose identity had been ascertained from the footage. Over 50 unknown people who had gathered in the prohibited zone are also on the radar of the police.

The police had detained RJD youth wing leader Akash Yadav and a few of his supporters for interrogation late Saturday night. They were released on Sunday on personal bonds. "They were let off as evidence didn't corroborate the charges levelled against them," a senior cop said.

The SSP said he would submit a detailed report to inspector-general (Patna zone) Nayyar Hasnain Khan in a day or two recommending disciplinary action against the personnel whose lapses led to the fracas in the restricted area.

Sources said many policemen who were deployed in the VIP area were not present at the spot when the incident occurred. "We have taken a serious note of the matter and will soon initiate steps to prevent recurrence of such an incident," the SSP said, adding that security around the Assembly has been tightened too.

Sources said the presence of Vinod Yadav, a resident of Beur in Patna, at the spot had shocked several JDU leaders.

Supporters of the rival JDU factions headed by Nitish Kumar and Sharad Yadav clashed outside the residence of the chief minister on Saturday. Riding two-wheelers, Sharad's supporters were escorting him to SK Memorial Hall from the airport when they stopped outside the chief minister's residence opposite Raj Bhavan and shouted slogans.

Trouble started when some of Sharad's supporters carrying sticks and belts tried to enter 1 Aney Marg.

Nitish's supporters, who had gathered there for the JDU's national executive committee meeting, came out and chased away the protesters.