Suspect's job was to help maintain Air Force's global communications network

The suspect accused of leaking classified documents was under surveillance for at least a couple of days prior to his arrest by the FBI on Thursday, according to a US government source familiar with the case.

The 21-year-old, who is a member of the Massachusetts Air National Guard, was expected to go to work Thursday where the FBI intended to take him into custody under more controlled circumstances, according to the source.

When the suspect did not go to work, agents who were already positioned outside his mother’s house, waited for the suspect to come out, the source said. This search and arrest effort accelerated when reporters for The New York Times knocked on the house door and spoke to people inside. 

The FBI is awaiting a search warrant for the mother’s residence as well as the father’s residence because the suspect spent time living at both locations, this source said.

Authorities expect to find numerous weapons in their search, based on photos posted on social media. The likely presence of weapons was one of the driving reasons the FBI did not want to make the arrest by raiding the house. Instead, agents waited for an opportunity to get him outside the house. 

Teixeira is taken into custody. (WHDH)

The FBI says it is still searching for evidence at a home in North Dighton, Massachusetts, where officers arrested a 21-year-old National Guard member for his alleged involvement in leaking classified US government and military documents.

Agents are likely looking through computers, hard drives, thumb drives, cameras and phones — anything that may have been used to capture and distribute classified documents, said John Miller, CNN's chief law enforcement and intelligence analyst.

Miller said he anticipates law enforcement will issue multiple search warrants at different residences connected to the suspect. He said the FBI may also seize weapons belonging to the suspect, Jack Teixeira.

Jack Teixeira is believed to be the leader of the chat group where a trove of classified documents were posted, multiple US officials told CNN.

The search for the suspect began with thousands of people who had access to the documents, but investigators were able to quickly narrow the search to potential members of the chat group with evidence collected in the days immediately following the discovery of classified documents online by US officials.

The first court appearance for Jack Teixeira will be tomorrow in Boston, according to the US Attorney’s office. The exact timing of the appearance will be announced tomorrow.

Teixeira, a member of the Massachusetts Air National Guard, has been arrested in connection with alleged unauthorized removal, retention and transmission of classified national defense information.

President Joe Biden was briefed on the FBI arrest of a suspect concerning the leaking of classified documents, according to a US official familiar with the matter. 

Biden, currently on his way to a banquet dinner in his honor at Dublin Castle, was briefed between his speech to the Irish parliament and his departure. He was at the hotel for roughly 90 minutes between the two events. 

Biden has been briefed regularly throughout the investigation, according to officials, and appeared to allude to how close law enforcement officials were to a possible arrest when he answered a question about the matter earlier Thursday in Dublin during a visit with the Irish president. 

The Air Force released service details for Airman 1st Class Jack Teixeira, who was arrested Thursday in connection to a leak of classified intelligence online.

Teixeira is an enlisted airman at the Massachusetts Air National Guard, who joined the service in September 2019, according to his service record. His official job is Cyber Transport Systems journeyman. According to the Air Force, Cyber Transport Systems specialists are tasked with making sure the service’s "vast, global communications network" is operating correctly.

The rank of Airman 1st Class is the third enlisted rank an airman will make. According to his record, Teixeira had earned one Air Force Achievement Medal, which is a relatively standard medal for airmen of that age and rank to receive. 

Teixeira was arrested in Massachusetts on Thursday. Attorney General Merrick Garland said he was arrested in connection with alleged unauthorized removal, retention and transmission of classified national defense information.

Attorney General Merrick Garland speaks to the press on Thursday. (Pool)

Attorney General Merrick Garland confirmed Thursday that Jack Teixeira, a member of the Massachusetts Air National Guard, was arrested in connection with the leaking of classified documents.

"FBI agents took Teixeira into custody earlier this afternoon without incident," Garland said at a news conference.

The arrest was connected to an investigation into "alleged unauthorized removal, retention and transmission of classified national defense information," Garland said.

The attorney general said Teixeira will be arraigned in a federal court.

Garland declined to answer questions.

Watch Garland's remarks here: 

CNN's Hannah Rabinowitz contributed reporting to this post.

Attorney General Merrick Garland is speaking now from Washington, DC, following reports that a member of the Massachusetts Air National Guard was arrested by the FBI on Thursday in connection with the leaking of classified documents that have been posted online.

The arrest of Jack Teixeira, 21, comes following a fast-moving search by the US government for the identity of the leaker who posted classified documents to a social media platform popular with video gamers.

Teixeira had been identified by The New York Times ahead of his arrest Thursday as the leader of the group where a trove of classified documents was posted.

As a member of the Massachusetts Air National Guard was arrested in connection with the leak of classified US documents, agents were seen in aerial footage directing the 21-year-old suspect to move toward an armored vehicle with his hands on his head. CNN's Josh Campbell said the apparent "overwhelming show of force" was used because of the suspect's background in the military.

Agents took extra precautions because the report disclosed him being a gun enthusiast, Campbell said.

The next steps, Campbell said, is investigating the residence of the suspect, which is now considered a crime scene.

"The feds will be there for a long time, because of course they need to determine: Are there additional classified documents that are inside that residence? [According to] what we've seen in past cases, the feds will get their search warrants lined up ahead of time in order to go in and search that top to bottom," he said.

Agents will be on the lookout for any location where a computer, a phone or digital files could be stored, Campbell said