A police vehicle was torched in Kolkata and officials of the force, including an assistant commissioner, were beaten up allegedly by Bharatiya Janata Party members during a protest march to the West Bengal secretariat building in Howrah on Tuesday.

Several BJP leaders were detained on Tuesday during the party’s march, ANI reported.

Among those detained include the Leader of Opposition Suvendu Adhikari, Locket Chatterjee, Taapshi Mondol, Rahul Sinha and Dibankar Gharami. The party’s state unit chief Sukanta Majumdar has also been taken into custody, reported ANI.

The police also lobbed tear gas grenades as protestors clashed with them. Kolkata councillor and former Deputy Mayor Meena Devi Purohit was injured in the clashes, reported The Indian Express.

The BJP held the march against the alleged corruption by the ruling Trinamool Congress. Hundreds of saffron party supporters from across the state arrived in Kolkata and neighbouring Howrah on Tuesday morning to take part in the ‘Nabanna Abhijan’ or march to the secretariat, according to NDTV.

This is the saffron party’s biggest campaign against the Mamata Banerjee-led Trinamool government since its defeat in the Assembly elections last year.

In videos of the protest march, men carrying BJP flags could be seen attacking the assistant police commissioner as he tries to flee. As protestors keeps attacking him, some men can be seen escorting him out of the conflict zone.

After Sinha was released, he said that he has sustained injuries on his head and hand, reported ANI. Describing the march as a democratic agitation, Sinha claimed that the demonstration turned violent as the police baton-charged them and used tear gas shells.

“We’ll continue the agitation until Mamata Banerjee leaves her seat,” he added.

West Bengal Police denied permission for the protest and imposed Section 144 of Code of Criminal Procedure that prohibits large gatherings around the secretariat building, The Indian Express reported. Several BJP workers from across the state were also detained by the police.

On Tuesday, Adhikari denounced the police action and alleged that West Bengal Chief Minister Mamata Banerjee was enforcing a dictatorship in the state.

“Mamata [Banerjee] doesn’t have the support of her people and so she is enforcing dictatorship, similar to North Korea in Bengal,” Adhikari told ANI. “The police will have to pay for what it has been doing since yesterday...BJP is coming.”

Visuals from ANI showed that police used water cannons and tear gas shells to disperse BJP workers in the Santragachhi town of Howrah.

Sinha alleged that Banerjee was trying to forcibly stop a “democratic protest” by his party.

He claimed that BJP supporters were prevented from boarding a train from Alipurduar to Sealdah last evening. “They were also lathicharged by the state police,” he said, according to NDTV.

Meanwhile, Trinamool Congress General Secretary Kunal Ghosh claimed that the saffron party had no strategy for the march.

“They do not have workers,” Ghosh said, according to The Indian Express. “The crowd you see is of police and media. Why didn’t Suvendu Adhikari sit on a dharna where he was stopped?”