According to the plea agreement, beginning in 2010 and continuing through March 2015, Pho removed and retained us government documents and writings that contained national defense information, including information classified as Top Secret and Sensitive Compartmented Information.
Harold T. Martin III, a Glen Burnie man and former NSA contractor, was indicted this year after being accused of stealing a "breathtaking" number of classified documents. Among the details of the case shrouded in mystery is the date he was charged.
However, from 2010 to March 2015, Pho had been removing classified USA data and bringing it home, knowing he had no authorization to do so.
Pho faces a maximum of 10 years in prison. Pho remains free while he awaits sentencing, which has been scheduled by US District Judge George L. Russell for April 6, 2018.
Pho is understood to be the Tailored Access Operations (TAO) programmer whose home computer was running Kaspersky Lab software that was allegedly used, one way or another, by Russian authorities to steal top-secret NSA documents and tools in 2015.
Pho held onto both physical, hard copies and digital copies of the documents, which were stored in his residence in Maryland.
In a November investigative report on the incident, Kaspersky Lab said its software had "inadvertently" retrieved the NSA tools because they were contained in a larger file that had NSA code in it that the firm classifies as malicious. Kaspersky has said it believes the NSA tools ended up with hackers when its client turned off his anti-virus software because it was preventing him from generating an encryption key. He declined to comment further.
And in 2013, former contractor Edward Snowden pilfered secrets about NSA's surveillance programs and shared them with journalists.
The charges come on the heels of another government investigation in relation to a larger breach of NSA security, in which the NSA's hacking tools were released to the public a year ago by an unidentified group called the Shadow Brokers, Wiredreported.
In June another NSA contractor, Reality Winner, 25, was charged with leaking classified material about Russian interference in the 2016 USA presidential election to a news outlet.
And Harold T. Martin III was arrested in 2016 after Federal Bureau of Investigation agents discovered some 50 terabytes of data and documents that Martin had taken from the NSA and other agencies over a period of 20 years. He has pleaded not guilty.