Mr Abdul Mannan, a senior Congress legislator, had to be rushed out on a stretcher.
Bengal is no stranger to violent protests where buses are burnt and government property is destroyed. But such actions will soon come with a price tag. The Mamata Banerjee government has just amended a law under which vandals would be made to pay for public property destroyed. The law has drawn ridicule from the opposition Left Front, which has pointed out that Ms Banerjee's own party has been guilty of such acts for years.
"We are not a weak government. We won't compromise on law and order or tolerate destruction of public property," Ms Banerjee has said. A fortnight ago, she had hinted at the new rules after mobs burnt six police vans in Bhangar and pushed four vehicles into a pond during protests against a power grid. The Maintenance of Public Order (Amendment) Bill was passed on Wednesday.
But the opposition held protests in the Assembly, reminding Ms Banerjee that her legislators had not spared even the Assembly building. The Left legislators held posters carrying photos from more than a decade ago, showing a group of legislators of Trinamool Congress - then in opposition -- going on a rampage after Ms Banerjee claimed she had been assaulted during the Singur agitation.
The Speaker asked the opposition to remove the posters, but the leader of Opposition Mr Abdul Mannan, a senior Congress legislator, allegedly walked into the well with one. When the marshals tried to evict him, he collapsed. Other legislators joined in the scuffle and at least one of the marshals has said he was assaulted. Mr Mannan had to be rushed out on a stretcher, into an ambulance and straight to hospital. Late in the evening news agency Press Trust of India reported that his condition is stable.
The opposition, which plans to meet the governor on the issue soon, is calling the new law "kala kanoon". "This is a black bill, completely undemocratic and an attempt to silence all opposition," said CPM member Sujan Chakraborty. "It is up to the police to handle public protests."
Trinamool leader Partha Chatterjee said, "Destroying government property, setting police vans on fire... for 34 years they did not do anything to stop it. But we want to give protection to the people of the state. Those opposing it are supporting loot, arson and a government that doesn't act".