Earlier, phone calls and e-mails could be intercepted only with the home ministry's permission.

Up to 9,000 phone calls and 500 e-mails were intercepted every month during the Congress-led United Progressive Alliance's rule in 2013, news agency ANI has quoted a Right To Information (RTI) response as saying.

"On an average, anywhere between 7,500 and 9,000 orders for interception of telephones are issued by the central government per month," the RTI response released in November 2013 stated. "Orders between 300 and 500 for the interception of e-mails are also issued on a monthly basis."

The application was filed by Prosenjit Mondal, a Delhi-based RTI activist.

This revelation gains significance in the light of protests against a directive by the Narendra Modi government authorising 10 central agencies to intercept and monitor data exchanged over the Internet, and even seize devices. While opposition parties termed this as an intrusion into people's privacy, the centre maintained that similar rules have been in existence since 2009.

Union Minister Rajyavardhan Singh Rathore Rajyavardhan Singh Rathore was quick to latch on to the RTI revelation, stating that the Congress should not be "hypocritical" about steps taken to ensure national security.

"As many as 9000 phones & 500 emails were tapped monthly in UPA-2, a 2013 RTI reveals. That's 300 phones & 20 emails tapped every single day. With its history of emergency & post office amendment bill, Congress should not be hypocritical about steps to ensure national security," he tweeted.

Protests against the centre's move even reached the Rajya Sabha on Friday, with Congress leader Anand Sharma accusing the government of trying to turn the country into a "surveillance state". Finance Minister Arun Jaitley hit back by saying that the Congress was "playing with the security of the country" and making "a mountain where even a molehill does not exist".

Earlier, only the home ministry could scan calls and emails of people. The new order empowers the Intelligence Bureau, Narcotics Control Bureau, Enforcement Directorate, Central Board of Direct Taxes, Directorate of Revenue Intelligence, CBI, National Investigation Agency, Cabinet Secretariat (Research and Analysis Wing), Directorate of Signal Intelligence (in Jammu and Kashmir, North-East and Assam only) and the Delhi Police Commissioner to do so too. The agencies can monitor not just calls or emails, but any data found on a computer, with the permission of the home secretary. Importantly, the agencies will also have powers to seize the devices, in the name of national security.

The opposition reacted sharply to the development. "Converting India into a police state isn't going to solve your problems, Modiji. It's only going to prove to over 1 billion Indians what an insecure dictator you really are," he tweeted soon afterwards.

Samajwadi Party leader Ramgopal Yadav termed it as a "dangerous" move. "All I would like to say is: We will see a change of government in the next few months. So it is best that the BJP doesn't dig a pit for itself," he said.

"Who knew that this is what they meant when they said Ghar Ghar Modi," tweeted AIMIM chief Asaduddin Owaisi.

(With inputs from ANI)