Hundreds of opposition Trinamool Congress workers led by Mamata Banerjee put up a road blockade near West Bengal Chief Minister Buddhadeb Bhattacharjee's residence late on Friday night demanding release of 18 agitators arrested by the police for indulging in violence to protest a court ban on two-stroke public transport vehicles.
Police stopped Banerjee and other Trinamool activists about 500 m from Bhattacharjee's Palm Avenue residence, prompting her to organize a sit-in demonstration at the spot.
An angry Banerjee wanted to know from the police why they were stopped. "There are no prohibitory orders here".
Demanding the immediate release of those arrested, Banerjee said, "Communist Party of India-Marxist (CPI-M) leaders can murder and sleep peacefully. I can't".
Banerjee put the blame for the torching of buses earlier in the day on the CPI-M, and said: "If they can prove we had set fire to the buses, I shall quit politics."
Earlier, slogan-shouting Trinamool activists led by Banerjee went round different parts of south Kolkata, and tried to go near Bhattacharjee's residence.
A large police contingent and Rapid Action Force personnel have been deployed in the area.
Expressing dismay at the Trinamool protests near Bhattacharjee's residence, senior CPI-M leader Shyamal Chakrabroty said: "It's a conspiracy. Never before has such sit-in protests been done before the chief minister's house. If this continues, a dangerous situation will be created in the state.
"They want lawlessness. They want police to use strong-arm tactics."
CPI-M state secretary Biman Bose announced his party would hold protest rallies Saturday morning against the Trinamool's "evil designs".
Another group of agitators, comprising auto union leaders, also tried to march towards the chief minister's residence but were stopped by the police 200m from the house.
The Calcutta High Court issued an order July last year to ban commercial vehicles registered before Jan 1, 1993, from Kolkata and its outskirts.
The court directed that all auto-rickshaws, irrespective of their date of registration, will have to convert to either compressed natural gas (CNG) or liquefied petroleum gas (LPG).
It said the order should be implemented by Dec 31, 2008, in the Kolkata Metropolitan Area, which includes parts of north and south 24-Parganas, Howrah and Hooghly.
It is estimated that around 80,000 auto-rickshaws, 24,000 taxis and over 8,000 buses and mini-buses would be affected by the implementation of the court order.