The Rajya Sabha on Wednesday witnessed a heated debate on the use of Electronic Voting Machines (EVMs), with the Congress demanding a ban since "these machines are not tamper-proof".

Leader of Opposition Ghulam Nabi Azad said, "Use of EVMs should be stopped right now. These EVMs should not be used in the April 23 civic polls in Delhi, coming assembly polls in Gujarat and other states."

The Rajya Sabha was even adjourned briefly over the issue after it was raised by Congress leader Digvijaya Singh.

Later, Samajwadi Party's Ram Gopal Yadav, Bahujan Samaj Party chief Mayawati and other opposition leaders also joined Digvijaya Singh and raised doubts on the EVMs.

"It's a serious matter," said Yadav.

Mayawati said the government was not "trustworthy" and her party will take the matter to court.

In response, members of the treasury benches said they must approach the Election Commission on the matter.

"Don't waste the time of the house," Minister of State for Parliamentary Affairs Mukhtar Abbas Naqvi said.

Naqvi said EVMs were used in many elections in the past and different political parties had won, but questions were raised only after the Bharatiya Janata Party won the Uttar Pradesh assembly elections in February-March.

"It's an insult to the people. It's also an insult to the Indian democracy," he said.

Deputy Chairman P.J. Kurien asked the members to maintain peace but nobody paid heed, following which he adjourned the upper house for eight minutes.