Google accuses FBI of 'spying' on its users

Google has accused the Federal Bureau of Investigation (FBI) of using National Security Letters (NSL) - a form of surveillance that privacy watchdogs call "frightening and invasive" - to secretly seek information on Google users.

NSL are a means for the FBI to obtain information on people from telecommunications companies, authorized by the Electronic Communications Privacy Act (ECPA) and expanded under the Patriot Act, reports Fox News.

NSL lets the agency seek information on a subscriber to a wire or electronic communications service, although not things like the content of their emails or search queries, Google said.

Electronic Frontier Foundation's Dan Auerbach and Eva Galperin said that the NSL power is one of the most frightening and invasive of all the dangerous government surveillance powers that were expanded by the USA PATRIOT Act.

They said that these letters allow the FBI to secretly demand data about ordinary American citizens' private communications and Internet activity without any meaningful oversight or prior judicial review.

The agency issued 16,511 National Security Letters in 2011. But Google was gagged from saying just how many letters it received - leaving key questions unanswered.

Richard Salgado, Google's legal director of law enforcement and information security, said people don't always use their services for good, and it is important that law enforcement be able to investigate illegal activity.

No other technology company presently disclose such basic information about government requests, experts noted.