Jack Teixeira, the 21-year-old soldier suspected of leaking a series of classified US documents about the war in Ukraine, was indicted in federal court on Friday, Reuters and AFP reported.

The Air National Guard employee was arraigned in federal court in Boston on Friday and charged with “unauthorized storage and transmission of national defense information” and “unauthorized removal and storage of classified documents or materials,” according to a court document.

Jack Douglas Teixeira of North Dayton, Mass., who was arrested by the FBI at his home Thursday without incident, appeared in federal court Friday wearing khaki overalls.

At the hearing, the top federal national security prosecutor in Boston, Nadine Pellegrini, asked that Teixeira be held pending trial, and a hearing was set for Wednesday.

The alleged leaks of classified documents were posted on social media earlier this year, but news of their existence was not reported until the New York Times reported them last week.

It is believed to be the most serious security breach since WikiLeaks released more than 700,000 documents, videos and diplomatic information in 2010.

U.S. officials are still assessing the damage from the leak, which included tapes purported to detail Ukrainian military vulnerabilities and information about allies including Israel, South Korea and Turkey.

Teixeira spoke only twice

Teixeira spoke only twice during the brief hearing in which he was charged, answering “yes” to a question about whether he understood his right to remain silent.

He also confirmed that he filled out a financial declaration that the judge said showed he was eligible to be represented by a federal public defender.

What punishment could he receive, given the WikiLeaks case

Anyone found guilty of intentionally passing on information about national defense faces up to 10 years in prison. Teixeira could face a longer term depending on the charges against him.

In the case of WikiLeaks, whistleblower Chelsea Manning was sentenced to 35 years in prison. Later, Democratic President Barack Obama commuted the sentence.

Last week, the Department of Justice opened a formal criminal investigation into the ongoing leaks, following a referral from the Department of Defense. The Pentagon said Thursday that the leak was a “deliberate criminal act,” adding that the military has taken steps to review mailing lists and ensure that only those who need it have access to the information.

It is unclear whether Teixeira has obtained legal representation.

Reuters reviewed more than 50 documents marked “Secret” and “Top Secret” but did not independently verify their authenticity. The number of leaked documents is likely to exceed 100.

The US is still trying to extradite WikiLeaks founder Julian Assange from London to face criminal charges over the 2010 leak.

Read also: What is known about Jack Teixeira and how the documents ended up on the Internet

How he got access to confidential information

Teixeira told members of his online Discord group that he was working as a member of the technical support staff at a base in Cape Cod, and through that he had access to classified documents.

Teixeira was stationed at Otis Air National Guard Base in Cape Cod, Mass., according to his military file. A squadron is located at the base, the tasks of which are related to intelligence services.

National Guard units provide some support services to military units, including intelligence support for the Joint Chiefs of Staff, according to The Washington Post.

Members of the Air National Guard’s 102nd Reconnaissance Squadron operate unmanned aerial vehicles that perform intelligence/surveillance/reconnaissance missions in support of the Air Force and ground combatants in locations such as Iraq, Afghanistan, Syria, and in support of special operations groups that can deploy secret missions anywhere.

That means units need access to a wide range of intelligence gathering and analysis because they can operate in multiple theaters against multiple threats, CNN reported.

Teixeira’s military listing indicates he enlisted in the National Guard on September 26, 2019. He was drafted into federal military service last fall, National Guard Bureau spokesman Nahaku McFadden told The Washington Post.

It is not unusual for National Guard members to receive such orders to meet the need for specialized work, and because the suspect was on active duty at the time of the alleged actions, he will be subject to additional punishment under the military justice system, the US newspaper said.

Lack of experience in accessing information

Although Teixeira was relatively inexperienced in the military, he had access to top-secret military intelligence through a Defense Department computer network known as the Joint Worldwide Intelligence Communications System (JWICS), a U.S. official told The Washington Post , familiar with this matter.

The system would allow Teixeira to read and possibly print classified documents, although there are directives to handle such material according to the law.

Thousands of military and government officials in even lower ranks likely had access to classified documents like the ones Teixeira allegedly shared, according to U.S. officials and experts who have seen the documents released to the press.

The military regularly entrusts young people with classified information and high responsibility, Pentagon spokesman Brigadier General Patrick Ryder acknowledged Thursday. “Think about a young platoon sergeant and the responsibility and trust we place in these men to lead troops into battle,” he said. “This is called military discipline,” the Pentagon representative emphasized.

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