• Harold Thomas Martin III, accused of stealing NSA clssified material.

Harold Thomas Martin III, accused of stealing NSA clssified material. (Photo : FBI)

Another contractor from Booz Allen Hamilton, Inc., the same firm Edward Snowden worked for, has stolen a huge trove of top secret documents, again from the National Security Agency (NSA), some of which he later sold online.

Government security experts said the haul of classified documents filched by Harold Thomas Martin III, 51, "could be expected to cause exceptionally grave damage to the national security of the United States."

Like Us on Facebook

Martin did technology work for Booz Allen Hamilton, an American management consulting firm headquartered in Virginia.

An NSA spokesman declined to comment on Martin's arrest.

Martin was arrested by the FBI in August and charged with theft of government property and unauthorized removal and retention of classified materials, authorities said.

Martin, who has top secret clearance, was arrested after FBI agents raided his home in Maryland. The investigators found documents and digital information stored on various devices containing highly classified information.

The FBI said among the classified documents found in Martin's home were six that contain sensitive intelligence dating back to 2014. This classification means the documents were produced through sensitive government sources or methods critical to national security. All the documents were clearly marked as classified information, said the FBI in affidavit accompanying the complaint.

Martin was apparently responsible for a baffling leak that led to NSA hacking tools being sold online in August. Among these tools Martin sold online included "exploits" that take advantage of unknown flaws in firewalls, allowing the government to control a network.

They were posted online by a group calling itself Shadow Brokers, which authorities believes is Martin himself.

Experts said the tools stolen and placed online by Martin could allow targets of NSA spying to determine they were being hacked by the NSA. Some foreign spy agencies might be able to reconfigure the tools to use against the NSA.

Rep. Adam B. Schiff (Calif.), the ranking Democrat on the House Intelligence Committee, said Martin's arrest made it "painfully clear that the Intelligence Community still has much to do to institutionalize reforms designed to protect in advance the nation's sources and methods from insider threats."

Booz Allen said it "immediately reached out to the authorities to offer our total cooperation in their investigation, and we fired the employee," upon again learning one of its employees was arrested for espionage.

"We continue to cooperate fully with the government on its investigation into this serious matter." The company claims there had "been no material changes to our client engagements as a result of this matter."

In 2013, Booz Allen contractor Edward Snowden gave journalists a plethora of documents revealing massive U.S. government surveillance programs that have faced criticism since they were revealed.

The complaint charges Martin with unauthorized removal and retention of classified materials, which carries a maximum one-year sentence, and theft of government property, an offense punishable by up to 10 years. If convicted, Martin faces a maximum of 11 years in prison. The U.S. attorney's office in Maryland said Martin appeared in court on Aug. 29.