Mamata, who is in Delhi to submit her plea with the Election Commission, asked her party leaders to make it a mass issue.

In the recent panchayat polls, the Election Commission used ballot papers and the Trinamool swept the elections in south Bengal and in some pockets of north Bengal.

The party leaders said that the results prompted Mamata to demand for ballot papers in the upcoming Lok Sabha elections.

She has alleged that the strong room where EVMs are kept before counting are manned by the state government employees and police.

“Ballot papers are used even in developed countries. The CPM is manipulating the machines and reversing the public mandate in Bengal. This year’s panchayat elections proved it,” said the Trinamool chief.

She further clarified that one of the reasons behind her party’s defeat in state Assembly elections in 2006 was manipulation of the machines.

“The expert committee set up by the EC observed on September 5, 2006 that there is a scope for manipulation in the machines,” added Mamata.

Debasish Sen, chief electoral officer of West Bengal, said: “It is not believable that EVMs can be tampered with. However, I cannot comment on her meeting with the Election Commission in Delhi.”