Police say agitators turned violent and wanted to force their way into House complex.

The police on Tuesday lathicharged teachers, whose protest near the Bihar Assembly complex took a violent turn leading to arson and stone-pelting. Five vehicles, including two police vehicles, were set on fire, while five more were damaged.

Caught on the back foot, the police used water cannon and lobbed tear gas shells to disperse the crowd, which included women. They also resorted to lathi charge and only after three hours were the police able to bring the situation under control.Hundreds of teachers and 10 police personnel were injured in the incident. Mr. Akhilesh Kumar, the general secretary of the Bihar Rajya Prathmik Sikshak Sangh (Association of Primary Teachers in Bihar), said the teachers’ organisations that participated in the protest will stage protests against Chief Minister Nitish Kumar across the State on Wednesday and declared a bandh from March 7. Teachers will strike work and boycott the upcoming matriculation exams, he said.

The Opposition also staged strong protests in both houses of the legislature against the “use of force” by the police.

Hundreds of newly appointed and contractual school teachers from three different organisations staged protest at R Block, near the Assembly premises demanding regularisation of service, equal pay for equal work and a common school system.

“They marched to the R Block and tried to break down the gate there. They wanted to force their way into the Assembly. They became violent and started pelting stones and damaging vehicles. The police applied force in retaliation,” Patna City Superintendent of Police Jayant Kant told The Hindu.

“They were shouting ‘Khagaria ka incident yaad hai?’, ‘Mukhiya ka incident yaad hai?’ [Do you remember the incident in Khagaria and the one related to the Mukhiya?],” Mr. Kant said. These were references to incidents of large-scale violence and arson in Khagaria district by contractual teachers and in Patna by Ranvir Sena chief Brahmeshwar Mukhiya’s supporters, which shook the State in 2012.

Mr. Kant said the police were not sure if antisocial elements were involved in the protests.

Around 50 protesters were arrested and booked under the Indian Penal Code Sections 147 (for rioting), 148 (rioting, armed with deadly weapon), 149 (related to unlawful assembly), 353 (assault or criminal force to deter public servant from discharge of his duty) and 307 (attempt to murder).

Meanwhile, the Association of Primary Teachers denied having indulged in violence. “We were staging a democratic protest, well within the regulations,” Mr. Akhilesh Kumar told The Hindu.

“We challenge the government to show us a recording of the protest. We were peacefully staging a protest, when the police suddenly started dragging away women teachers and began a lathi charge. About the incident of stone-pelting and arson, we have no idea who did it,” Mr. Kumar said.

Apart from his organisation, two others — the Bihar Panchayat-Nagar Prathmik Sikshak Sangh and the Nau-Niyukt Madhyamik Sikshak Sanghatan (Newly-appointed Teachers’ Association) — staged a demonstration under the banner of the Bihar Rajya Shikshak Sangharsh Morcha.

R.A. Singh, the Joint Director of Primary Education said there were “no contractual teachers” in his department, only “teachers who were appointed under different rules.”

Earlier teachers were appointed from the district cadre, while the newer appointments have taken place under the Panchayati Raj institutions, which have a fixed pay scale. They have leave and other provisions and are as good as regular teachers. The government has appointed these teachers as per its resources under the service rules.

“Teachers appointed by the Panchayati Raj institutions have a lower pay scale. They have been demanding pay parity,” Mr. Singh told The Hindu. There are about 2.42 lakh newly appointed teachers and one lakh from the district cadre in primary education.