TMC leader Abhishek Banerjee on Tuesday alleged large-scale irregularities in the West Bengal assembly polls, questioning the counting process as well as the role of election officials and security forces.

Speaking to reporters after attending a press conference addressed by party supremo Mamata Banerjee at Kalighat, he claimed that while votes recorded in EVMs might remain intact, the machines themselves could be replaced, changing the original figures.

"The way rigging has taken place in the election... votes recorded through EVMs may not be manipulated, but EVMs themselves can be replaced," he alleged.

The Diamond Harbour MP alleged that the election outcome was influenced by "systematic irregularities" that led to the TMC's defeat.

"Multiple complaints were filed during counting and shared with officials, but no action was taken," he alleged.

Banerjee also alleged inconsistencies between the serial numbers of EVMs brought to the counting tables and the records in Form 17C.

He questioned how machines used for long hours showed "unusually high battery levels" of over 90 per cent.

Asked about the presence of returning officers, micro-observers, counting agents and central forces personnel during the counting, he claimed their deployment alone did not guarantee transparency.

"There can still be possibilities of malpractice," he alleged.

"I demand that CCTV recordings covering the full counting day, particularly between 12 pm and 6 pm, be released in the interest of transparency," he said, alleging that counting was deliberately slowed during the afternoon hours.

Banerjee, who is the nephew of the TMC supremo, said the party would review the issues internally and set up a fact-finding team.

He also alleged that widespread violence happened in the aftermath of the results, claiming that 300 to 400 party offices were vandalised across the state by BJP supporters "in the name of celebration".

He also claimed that the house of the winning TMC candidate, Bina Mondal, was ransacked and her car damaged at Swarupnagar in North 24 Parganas district.