U.S. secretly tracked billions of calls for decades

The U.S. government started keeping secret records of Americans' international telephone calls nearly a decade before the Sept. 11 terrorist attacks, harvesting billions of calls in a program that provided a blueprint for the far broader National Security Agency surveillance that followed.

For more than two decades, the Justice Department and the Drug Enforcement Administration amassed logs of virtually all telephone calls from the USA to as many as 116 countries linked to drug trafficking, current and former officials involved with the operation said. The targeted countries changed over time but included Canada, Mexico and most of Central and South America.

Federal investigators used the call records to trac