(CN) - The National Security Agency ran a pilot project to learn the location of Americans' cellphones but never completed the program, the agency's intelligence director told the Senate Judiciary Committee.
The secret project, in 2010 and 2011, used data from cellphone towers to find people's cellphones.
James Clapper revealed little during his testimony, the New York Times reported. But he did testify that the NSA does not collect location information because it is barred under Section 215 of the Patriot Act.
The law allows the NSA's once-secret program to collect information of all Americans' telephone calls.
"In 2010 and 2011, NSA received samples in order to test the ability of its systems to handle the data format, but that data was not used for any other purpose and was never available for intelligence analysis purposes," Clapper said.
The intelligence director also vowed to notify Congress and get approval from the once-secret Foreign Intelligence Surveillance Court before attempting to collect any more locational data.
The New York Times first exposed the secret pilot project on Wednesday, and Clapper later confirmed it. The article was based on documents leaked by former NSA contractor Edward Snowden.
The article said the agency allowed for "contact chaining" of Americans who have been communicating with foreign intelligence suspects via phone and email data.
It also detailed how data from social networks is used for data "enrichment" to flesh out profiles.
But Sen. Ron Wyden, D-Ore., who sits on the Intelligence Committee, said in a statement that there is more to the program than the government is saying.
"After years of stonewalling on whether the government has ever tracked or planned to track the location of law-abiding Americans through their cell phones, once again, the intelligence leadership has decided to leave more of the real story secret - even when the truth would not compromise national security."
Sen. Patrick Leahy, D-Vt., said he's writing a law to stop the NSA from systematically getting call records.
Meanwhile, Senate Intelligence Committee chairwoman Sen. Diane Feinstein, D-Calif., vowed to do "everything I can to prevent this program from being canceled out," the Times reported.
It's still not known how many Americans' cellphones were tracked, or how the data were used.
Clapper also told the committee on Wednesday that the current government shutdown brought on by a budget and health care gridlock "seriously damages" national security.
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