Bengal Chief Minister and TMC supremo Mamata Banerjee on Tuesday sat on a dharna in the heart of the city to protest against the Election Commission's "unconstitutional" decision to ban her from campaigning for 24 hours.

Banerjee, still confined to a wheelchair owing to the injuries she sustained last month, arrived at Mayo road here around 11.40 am and began her sit-in next to a Mahatma Gandhi's statue at the venue.

No TMC leaders or supporters were spotted nearby.

A senior TMC leader, when approached, said, "No party leaders are allowed near the site of the protest. She is sitting there alone."

The Election Commission has barred Banerjee from campaigning for 24 hours from Monday 8 pm for her remarks against central forces and a statement which had alleged religious overtones.

Banerjee, lashing out at the poll panel, had said on Twitter that she would hold a protest against the poll panel's "unconstitutional and undemocratic" decision.

The TMC boss is scheduled to address two rallies after 8 pm on Tuesday -- one at Barasat and the other at Bidhanangar.

Mamata had tweeted after the poll panel ban on campaigning: “To protest against the undemocratic and unconstitutional decision of the Election Commission of India, I will sit on dharna tomorrow at Gandhi Murti… from 12 noon.”

Derek O’Brien, the Trinamul Congress leader in the Rajya Sabha, said: “You can ban us but you can’t beat us.”

Announcing the campaign ban on Mamata, Election Commission secretary Rakesh Kumar had said: “Ms Banerjee in her reply has yet again conveniently left out key parts of her speech, perhaps due to selective amnesia….”

Meanwhile, a defence official here said that the area where Banerjee is staging a protest belongs to the army, and the TMC was yet to receive permission for the programme.

"Just to keep everyone informed, we have received an application from the TMC for a no-objection certificate at 9:40 am today. It is still under process," the defence spokesperson said.