NSA

A former employee at the National Security Agency has been sentenced to five and a half years in prison for taking top US defense files to his home.

Nghia Hoang Pho, 64, was sentenced Tuesday after pleading guilty in December to willful retention of national defense information, the US Justice Department said in a statement. The charges carried a maximum sentence of 10 years, but prosecutors had recommended a sentence of eight years.

Pho, a naturalized US citizen originally from Vietnam, worked in the NSA's Tailored Access Group, the agency's team that focuses on tools that can directly hack surveillance targets. Between 2010 and March 2015, Pho took home paper and digital copies of US government documents and writings that contained national defense information on them, the Justice Department said.

Pho reportedly had antivirus software from Kaspersky Lab on his home computer network and the software scooped up the top secret information as part of its virus scanning process. Kaspersky has acknowledged that its software lifted hacking tools from a home computer in 2014 but said it wasn't part of an intentional effort to steal information from the NSA.

The company's products have been banned from government computers and pulled from the shelves by electronics retailer Best Buy.

Pho said in court he took the materials home so he could put in more work to earn a promotion, according to CBS Baltimore.

The security lapse is just the latest in a series of high-profile headaches to rock the NSA in recent years. In 2013, former NSA contractor Edward Snowden leaked documents detailing the ways in which the secretive US government agency was collecting data. Last month, Reality Winner, a former NSA contractor, was sentenced to more than five years in prison for leaking classified government information to the media.

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