The FBI acknowledged Wednesday it had arrested a National Security Agency contractor on charges of stealing highly classified information and is investigating possible links to a recent leak of secret hacking tools used to break into the computers of adversaries.

The Maryland home of 51-year-old Harold Thomas Martin III (pictured) was raided by FBI agents last month after he allegedly admitted to having taken government secrets, authorities said.

"Martin at first denied, and later when confronted with specific documents, admitted he took documents and digital files from his work assignment to his residence and vehicle that he knew were classified," the Department of Justice affidavit alleges. "Martin stated that he knew what he had done was wrong and that he should not have done it because he knew it was unauthorized."

The documents do not detail the classified information that the agency says it seized, but the move does correspond to a cyberleak of purported malicious hacking tools used by the NSA to tamper with firewalls, the electronic defenses protecting computer networks, which was pulled off by a group calling itself the "Shadow Brokers."

The complaint does not reference that group or allege a link to Martin, and a defense attorney said Martin never intended to betray his country. But the disclosures were the most significant leak since the disclosures made by NSA contractor-turned-fugitive Edward Snowden in 2013 .

NSA General Counsel Glenn Gerstell told the Reuters news agency that the NSA was still assessing damage from the data theft, but said: "I don't think this is a Snowden-type situation." Snowden, who has been granted asylum in Russia, said he deliberately exposed the scope of US government surveillance to force changes. The leaks and subsequent arrest are another embarrassment for the US intelligence community.

(DW)