Congress leader Digvijaya Singh on Friday questioned the infallibility of electronic voting machines (EVMs) saying there is no machine with a chip that cannot be hacked, and asked supporters of opposition parties to remain vigilant.

Singh also alleged that the ruling BJP may manipulate the electoral roll to add "ghost voters".

He was speaking at a meet -- "Jeetega INDIA: National Convention for Democracy, Secularism and Social Justice" -- organised by the Bharat Jodo Abhiyan (BJA) and the Confederation of Indian Communists and Democratic Socialists here.

"How to combat the ground force of the BJP? By just manipulating voters' list they can do a fraud of 5-10 per cent. They have a powerful mechanism for adding ghost voters in the list which is remarkable," Singh said.

"In polling booths where they are weak, they may add ghost voters and cut out genuine ones. There are examples of a single household having 150 voters," he claimed.

On EVMs, he said, "There is no machine which has a chip that cannot be hacked. How this can be controlled depends on the ECI (Election Commission of India) and us." Singh, a former chief minister of Madhya Pradesh, said all EVMs should have voter verifiable paper audit trail.

"Why not have a slip from the electronic machine which is put into a box? There are some assemblies where we win by 40,000 votes and then after a few months, we lose the same seat by 40,000 votes in Lok Sabha. They don't do this on every seat but do it selectively," he alleged.

Noting that not much time is left before the Lok Sabha elections, Singh said if the opposition does not start fighting on the ground, it will not be effective.

"(Prime Minister Narendra) Modi ji will say INDIA alliance has been formed because they hate Modi ji. But our fight is not against Narendra Modi, but against the ideology which is dividing India, which is destroying democracy," he said.

Addressing the meet, Communist Party of India (Marxist-Leninist) Liberation leader Dipankar Bhattacharya said the Indian National Developmental Inclusive Alliance (INDIA) should start its campaign and hold rallies at the earliest.

"This time is very important. Even today there is no big movement or rally which INDIA has initiated. A movement has to be created," he said, calling for unity among the alliance partners as seen during India's freedom struggle.

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