Jack Teixeira, the 21-year-old Massachusetts Air National Guardsman accused of leaking documents the Department of Defense says contain "sensitive and highly-classified material," was charged Friday with unauthorized retention and transmission of national defense information and willful retention of classified documents, according to Fox News.

Teixeira was read the charges shortly after 10:00 a.m. local time during an appearance in federal court in Boston. He did not enter a plea and was ordered to be held pending a detention hearing set for Wednesday, according to the US Attorney's Office for the District of Massachusetts.

The appearance at the federal courthouse comes a day after Teixeira was taken into custody by the FBI at his home in North Dighton, Massachusetts.

A criminal complaint obtained Friday by Fox News says the FBI on Monday interviewed a member of a social media platform who told a special agent that an individual — later identified to be Teixeira — began posting on the platform "what appeared to be classified information" starting in December 2022. The postings, the person said, appeared on a group aimed at discussing "geopolitical affairs and current and historical wars."

The person said the individual first started sharing paragraphs of text, but around January of this year began posting images of documents that appeared to have classification markings on them.

One of the documents, prosecutors say, "described the status of the Russia-Ukraine conflict, including troop movements, on a particular date" — information that is "based on sensitive U.S. intelligence, gathered through classified sources and methods, and contains national defense information."

The person said he engaged in conversations with Teixeira and at one point, the young man "explained that he had become concerned that he may be discovered making the transcriptions of text in the workplace, so he began taking the documents to his residence and photographing them."

Teixeira joined the Air National Guard in September 2019 and worked as a cybersecurity systems journeyman, a position in which he held the highest-level security clearance granted by the federal government for top secret information, according to an internal Department of Defense email reviewed by Fox News.

His security clearance and access to classified government systems have since been revoked, according to another internal government document.

Teixeira was most recently stationed at Otis Air National Guard Base in Cape Cod as a member of the 102nd Intelligence Wing. He was promoted to airman first class in July, according to the unit.

One of the leaked top-secret documents contained a short paragraph about Israel and alleged involvement by Mossad officials in the protests against the government’s judicial overhaul.

Another top-secret document that was leaked contained a US intelligence analysis of Israeli policy regarding military aid to Ukraine and stressed that US pressure could drive Israel to deliver more military assistance to Kyiv.

On Monday, a top Pentagon spokesman said that the online leaks of scores of highly classified documents a "very serious" risk to national security, and senior leaders are quickly taking steps to mitigate the damage.

(Israel National News' North American desk is keeping you updated until the start of Shabbat in New York. The time posted automatically on all Israel National News articles, however, is Israeli time.)