Jack Teixeira, the Air National Guardsman accused of leaking highly classified military documents on social media, pleaded not guilty in a Massachusetts court Wednesday to six federal charges, CNN reported.

Teixeira, 21, was indicted earlier this month on several counts of willful retention and transmission of classified information related to the national defense. He has been held in federal custody since his arrest in April.

The Massachusetts native stands accused of sharing classified military documents on the social media platform Discord.

According to prosecutors, Teixeira, a junior enlisted airman who worked within the Massachusetts Air National Guard’s 102nd Intelligence Wing, began posting information about the documents online around December 2022, and photos of documents in January.

Teixeira held a top-secret security clearance, and internal Air Force memos that prosecutors highlighted in court revealed that his superiors repeatedly warned him about inappropriately accessing classified intelligence.

Lawyers for Teixeira have argued in court that their client didn’t expect classified information that he posted on Discord to be further spread around the internet.

Teixeira was taken into custody by the FBI at his home in North Dighton, Massachusetts in April. A judge last month ordered him to remain jailed as he awaits trial, saying that releasing Teixeira would pose a risk that he would attempt to flee the country or obstruct justice.

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.