Suspect in U.S. military intelligence leak expected to appear in court today in Boston

A 21-year-old member of the US Air National Guard suspected of leaking classified military intelligence records online will make his first appearance before a federal judge in Boston on Friday.

Jack Douglas Teixeira, of North Dighton, Mass., was arrested by the FBI at his home on Friday without incident.

The leaked classified documents at the center of the investigation were posted online on social media websites in March and possibly earlier, but word of their existence was not known until reported by the New York Times last week.

It is considered the most serious security breach since more than 700,000 documents, videos and diplomatic cables appeared on the WikiLeaks website in 2010.

US officials are still assessing the damage caused by the leaks, which include records that reveal details of Ukraine’s military vulnerabilities and information about allies including Israel, South Korea and Turkey.

Although the charging documents for Teixeira have not been made public, US Attorney Merrick Garland said on Thursday that he was arrested in connection with an “investigation into the unauthorized removal, retention and transmission of national defense information.”

Dozens of documents have been found so far

Anyone found guilty of knowingly transmitting national defense information faces up to 10 years in prison. Teixeira could potentially face a longer sentence depending on what charges are brought against him.

In the case of WikiLeaks, the leaker – US Army Private First Class Chelsea Manning – was sentenced to 35 years in prison. Former US president Barack Obama later changed the sentence.

The Justice Department opened a formal criminal investigation last week into the current leak, following a referral from the Defense Department. The leak was a “deliberate criminal act,” the Pentagon said on Thursday, adding that the military had taken steps to review the distribution list and ensure that those who received the information were aware of it.

It is unclear whether Teixeira has yet to obtain legal representation.

Reuters has reviewed more than 50 of the documents, labeled “Secret” and “Top Secret,” but has not verified their authenticity. The number of leaked documents is likely more than 100.

The US is still fighting to extradite WikiLeaks founder Julian Assange from London to face criminal charges related to the 2010 leaks.

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