The government pressed social media websites including Facebook and Twitter to remove "inflammatory" content it said helped spread rumours that caused an exodus of migrants from some cities last week.
The government said in a statement it had already blocked access to 245 web pages, it said, contained doctored videos and images, and the telecommunications secretary, R Chandrashekhar, threatened legal action against the websites if they did not fully comply with the requests to take down the offending pages.
Chandrashekhar told TV channel CNN-IBN that Google and Facebook had largely complied with the government's requests while the response from Twitter had been "extremely poor", though he added that this "may be in part because they don't have an office in India".
"A lot of inflammatory and harmful content/information has been found to be appearing on the social networking sites hosted outside the country," the government statement said.
We asked our readers their take on this whole episode, whether they think is it correct to blame social media for North East exodus or not.
57.27% of respondents didn't blame social media for the exodus, 37.27% felt social media is responsible for the exodus of people from North East while less than 6% respondents chose not to answer in yes or no.
The government met representatives of social media sites on Friday to push its case, it said.
Twitter said it was "now actively reviewing" the request and will be seeking additional information from the Ministry of Communication and IT "to locate the unlawful content and the specific unlawful tweet", they said.
Earlier, the PMO had asked the Cyber Security Cell of the Department of IT to block these accounts as these had content having "communal overtones" and could have serious ramifications as these could be mistaken as the official account of the PMO.
The PMO had initially asked the Twitter to shut down these accounts but after it was not done, the matter was referred to the Cyber Security Cell.
The crackdown will likely rekindle a debate on freedom of speech and censorship of the internet in the world's largest democracy.
Media group Reporters Without Borders said in March that India was increasing pressure on internet service providers to supply users' personal data.
Google says that between July and December 2011 there was a 49% jump in requests from India for content to be removed from its services, compared to the previous six-month period.
In a move that will likely add to their concerns, the government on Tuesday blocked a number of Twitter accounts that spoof the prime minister, local media reported.
"The government is for free information. There is no question of anything being censored here. But that does not mean there are not limitations," a senior official in the ministry of home affairs said, adding that authorities were trying to identify those responsible for posting the inflammatory material.
Thousands of students and workers from the northeast fled Mumbai, Bangalore and other cities last week fearing retaliation for violence against Muslims in Assam after threatening mobile phone text messages and website images sowed panic.
Clashes between indigenous people in Assam and Muslim settlers from neighbouring Bangladesh have killed at least 80 people and displaced some 300,000 since July.
India blames Pakistan
A cyber law expert said blocking web pages was "like putting a band-aid on a leaking roof".
"It's a strategy that is doomed to failure from the word go. There are so many indirect ways to access the Net," said Pavan Duggal.
India has not released details of the blocked pages but said in a statement that "international social networking sites" had indicated that much of the content had been uploaded from neighbouring Pakistan, a long-time foe with which it has fought three wars.
An industry executive, who did not wish to be named, said companies "cannot share such information with the government".
"It's beyond their jurisdiction. This is an international issue, which the government is well aware of," said the executive.
Google and Facebook said they were cooperating with the government.
"We have received requests from Indian authorities and agencies and are working through those requests and responding to the agencies," Facebook said in a statement released by their Indian representatives.
Google has accepted the government's request to take down some content, while discussions are continuing on other requests, said a source with knowledge of the developments.
"We understand the gravity of the situation, strongly condemn acts of violence and continue to work closely with relevant authorities," Google spokeswoman Paroma Roy Chowdhury said in a statement.Media reports said many of those panicked by the fear-mongering text messages and internet postings have begun returning home this week.
Respect internet freedom: US to India
Voicing its support for full freedom of the internet, US has urged India to maintain respect for fundamental freedoms, while probing rumours that have caused an exodus of northeastern Indians from southern cities.
The US "have seen these reports that northeastern Indians are returning to the northeast from cities in southern India, and these media reports that the returns are due to concerns about personal safety", State Department spokesperson Victoria Nuland told reporters Tuesday when asked about India blocking some websites for allegedly orchestrating a campaign of hatred.
"On the larger question of internet freedom, you know where we are on that issue, and we are always on the side of full freedom of the internet," she said.
"But as the Indian government continues to investigate these instances and preserve security, we also always urge the government to maintain its own commitment to human rights, fundamental freedoms, rule of law."Asked to explain its stand on WikiLeaks in view of its professed support of full freedom of the internet, Nuland said: "WikiLeaks didn't have to do with freedom of the internet. It had to do with the compromise of US government classified information."
The US had not asked for any investigation by the Indian government nor was it part of the investigation, Nuland said, noting that India itself has "called an investigation of some of the sources of the rumours that have caused people to start to move".
"And so we are going to obviously watch and see how that process goes forward," she said.
Asked if the US had or would ask US-based companies, including Google, Facebook, and Twitter to comply with Indian government's directive to go after the sources of erroneous information, Nuland said she could not speak "of the conversation that those companies may or may not be having with the Indian government".
"We maintain open lines to our own companies in India, as we do around the world, and we are obviously open to consultation with them if they need it from us," she said.
(With inputs from Reuters, IANS)