Mike Snider

USA TODAY

The U.S. government threatened Yahoo with daily fines of $250,000 for refusing to hand over user data as part of the National Security Agency's surveillance programs, Yahoo said Thursday.

The Foreign Intelligence Surveillance Court of Review released more than 1,500 pages of previously secret documents related to Yahoo's 2007 challenge to the government's demand for data, the company's general counsel Ron Bell said on Yahoo's Tumblr page.

No documents were available immediately, but Yahoo is in the process of making them all public, he said.

Back in 2007, after the government "amended a key law to demand user information from online services ... we refused to comply with what we viewed as unconstitutional and overbroad surveillance and challenged the U.S. government's authority," Bell said.

But Yahoo lost that initial challenge and an appeal. The rulings against Yahoo bolstered the government's argument that national security concerns legally justified the collection of user data from tech firms.

News broke last June about the National Security Agency and the FBI siphoning of personal data from the main computer servers of nine major U.S. Internet firms including Facebook, Google and Microsoft, as reported by The Post and the London-based Guardian, with documents provided by Edward Snowden.

Apple, Facebook, Google and Microsoft did not have immediate comment.

Portions of some released documents remain classified and Yahoo is pressing the court to agree to make those public, as well as other documents that are still classified.

"We treat public safety with the utmost seriousness, but we are also committed to protecting users' data," Bell said. "We will continue to contest requests and laws that we consider unlawful, unclear, or overbroad."

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