NSA tested phone tracking.

Byline: Kimberly Dozier and Stephen Braun

5The tests: Alexander told the committee that his agency once tested, in 2010 and 2011, whether it could track Americans' cellphone locations, but he says the NSA does not use that capability, leaving that to the FBI to build a criminal or foreign intelligence case against a suspect and track him.

5The collections: Alexander acknowledged his agency collects data from social networks and other commercial databases to hunt foreign terror suspects, but is not using the information to build private files on Americans.

WASHINGTON -- National Security Agency chief Gen. Keith Alexander revealed Wednesday that his spy agency once tested whether it could track Americans' cellphone locations, in addition to its practice of sweeping broad information about calls made.

Alexander and Director of National Intelligence James Clapper testified at a Senate Judiciary Committee hearing on proposed reforms to the NSA's surveillance of phone and Internet usage around the world, exposed in June by former NSA analyst Edward Snowden. But neither spy chief discussed proposed reforms; instead they were questioned about new potential abuses that have come to light since then.

Alexander denied a New York Times report published Saturday that said NSA searched social networks of Americans searching for foreign terror connections, and detailed 12 previously revealed cases of abuse by NSA employees who used the network for unsanctioned missions like spying on a spouse. He said all employees were caught and most were disciplined.

Alexander and Clapper also told lawmakers that the government shutdown that began Tuesday over a budget impasse is seriously damaging the intelligence community's ability to guard against threats. They said they're keeping counterterrorism staff at work as well as those providing intelligence to troops in Afghanistan, but that some 70 percent of the civilian workforce has been furloughed. Any details on the jobs held by the furloughed employees is classified.

Congress is mulling changes to the Foreign Intelligence Surveillance Act that some believe allows the NSA too much freedom in gathering U.S. data as part of spying on targets overseas.

Alexander told the committee that his agency once tested, in 2010 and 2011, whether it could track Americans' cellphone locations, but he says the NSA does not use that capability, leaving that to the FBI to build a criminal or foreign intelligence case against a...