The National Security Agency destroyed surveillance data it pledged to preserve in connection with pending lawsuits and apparently never took some of the steps it told a federal court it had taken to make sure the information wasn't destroyed, according to recent court filings.

Word of the NSA's foul-up is emerging just as Congress has extended for six years the legal authority the agency uses for much of its surveillance work conducted through U.S. internet providers and tech firms. President Donald Trump signed that measure into law Friday.

Since 2007, the NSA has been under court orders to preserve data about certain of its surveillance efforts that came under legal attack following disclosures that President George W. Bush ordered warrantless wiretapping of international communications after the 2001 terrorist attacks on the U.S. In addition, the agency has made a series of representations in court over the years about how it is complying with its duties.