Image source, Reuters

CBS, the BBC's US partner, has obtained Teixeira's service record.

According to the record, Teixeira is an Airman 1st Class based at Otis Air National Guard Base, which is located on Western Cape Cod.

He has been in the Air National Guard since September 2019.

His official title is "Cyber Transport Systems Journeyman".

The Air Force's official website notes that personnel assigned to Cyber Transport Systems jobs are responsible for operating the Air Force's huge global communications network, which links units operating both in the US and overseas.

Defence officials have said that such assignments could include the repair of network hubs in the US or fiber-optic communications systems at facilities abroad, for example.

Teixeira's service record does not suggest any overseas deployments.

He has, however, been awarded an Air Force Achievement Medal, which is given for "outstanding achievement or meritorious service rendered specifically on behalf of the Air Force", according to the service.

Mike Wendling

Image source, WBZ

From the moment the leak of classified documents was revealed in the mainstream media last week, it seemed likely that the alleged leaker would be caught.

Open-source experts - journalists and researchers who study publicly available material online - noticed stray objects in the backgrounds of photos of hastily folded paper printouts.

The objects and the printouts did not throw up obvious clues, but they did point to a sloppy, less-than-professional method of operating.

Over the last 24 hours, interviews in the Washington Post, external and the New York Times, external with online associates of the suspect gave us further information about his possible identity.

One of the big questions is motivation.

Members of the chat room say that the alleged leaker wasn't driven by politics, and instead was just trying to impress his friends. We'll surely hear more about that soon.

Jack Teixeira is expected to make his first appearance in court on Friday in Boston, the US attorney’s office has said according to multiple US media reports.

Teixeira, a 21-year-old US Air Force National Guard member, was arrested earlier today by the FBI, which believes he is linked to a leak of confidential US defence and intelligence documents.

Image source, Reuters

Here's more key takeaways from the cache of classified US documents leaked online:

• Western forces in Ukraine: One document refers to the presence of a small number of Western special forces operating inside Ukraine, without specifying their activities or location
• Ukraine offensive: According to the Washington Post newspaper, one document expresses misgivings about Ukraine's chances of success in its forthcoming counteroffensive
• Russian rockets: A document revealed Egypt had plans to produce 40,000 rockets for Russia in secret. President Abdul Fattah al-Sisi reportedly told officials to keep production and shipment secret
• South Korea torn over Ukraine support: A classified document reveals that South Korea was torn about selling weapons for use in Ukraine
• Chinese weapon tests: The Post also found that Beijing tested one of its experimental missiles - the DF-27 hypersonic glide vehicle - on 25 February

Read more: What the leaked Pentagon documents reveal

The leaked documents, which first appeared on messaging app Discord, paint a detailed picture of the war in Ukraine and information on China and allies. These are some of the key findings:

• UN boss 'too accommodating' to Russia: UN boss Antonio Guterres was too willing to accommodate Russian interests, according to files which suggest Washington has been closely monitoring him
• Chinese retaliation: Documents based on intelligence from late February detail discussions among senior Jordanian officials over whether or not to shut Chinese firm Huawei out of its 5G rollout plans. Jordan's Crown Prince Hussein is said in the document to be worried about retaliation from China
• Ukraine casualties: Documents suggest Russian officials are at loggerheads over the reporting of casualties

You can read more of our analysis here.

Image source, Facebook

Jack Douglas Teixeira was arrested on suspicion of allegedly leaking highly sensitive US intelligence documents, according to US officials.

So, what do we know about him?

• He is an employee of the United States Airforce National Guard

• Someone with his name was allegedly a leader of an online gaming chat group on Discord where the files were leaked
• He is 21-years-old and was arrested in North Dighton, Massachusetts
• He was described "as a young gun enthusiast who works at a military base" in The Washington Post, who published an interview, external with a member of the chat room

Read more about what we know about the suspect here.

Watch as Attorney General Merrick Garland announces the arrest of Jack Teixeira in connection with the documents leak.

Barbara Plett Usher
North America correspondent

The Pentagon has called the leak a “serious risk” to national security and the White House is taking it “extremely seriously”, but President Biden says the classified documents did not compromise intelligence “of great consequence”.

All can be true. The leaks helped paint a detailed picture of the war in Ukraine and revealed sensitive secrets about both allies and adversaries.

But not battlefield plans: the documents were a snapshot, now over a month old, of the conflict from the US perspective. Experts don’t expect a direct impact on future Ukraine offensives.

Top US officials are working hard at controlling the diplomatic fallout from the spying revelations. But allies have continued to share information after leaks in the past, and are expected to continue to do so, although perhaps more warily.

The most serious outcome could be on intelligence gathering – the leaks indicated extensive US penetration of the Russian military that might put American sources at risk.

Image source, WBZ

Footage shows the moment Jack Teixeira was arrested at his home in Dighton, Massachusetts.

The suspect in the leaked classified documents case is seen backing up towards a large armoured vehicle, with his hands above his head.

A group of about half a dozen armed officials in military-style green fatigues surround and handcuff him and appear to place him in the back of the van.

He appears to be wearing red basketball shorts and a T-shirt.

Image source, WBZ

The FBI has released a statement on the arrest and confirmed that it took 21-year-old Jack Douglas Teixeira into custody for "alleged involvement" in leaking classified government documents.

The FBI's statement said that it is still conducting "law enforcement activity" at a residence in North Dighton, Massachusetts.

"Since late last week the FBI has aggressively pursued investigative leads and today's arrest exemplifies our continued commitment to identifying, pursuing, and holding accountable those who betray our country's trust and put our national security at risk," the statement added.

Image source, Getty Images

We now know that Jack Teixeira, a member of the Massachusetts Air National Guard, has been arrested in connection with the leaked documents.

However, we still don't know exactly what he will be charged with.

A short while ago, Attorney General Merrick Garland shared a short statement saying only that Teixeira was arrested in connection with alleged "unauthorised removal, retention and transmission" of classified defence information.

At the Pentagon briefing earlier, General Pat Ryder said that the leak was a "deliberate criminal act" and violation of protocols governing the handling of classified materials.

We'll learn more once Teixeira makes his initial court appearance.

The first screenshots of the leaked classified documents we've been able to verify were posted on 1 March on Discord, a social media platform popular with gamers. They were then shared on several discussion channels.

These channels aren't about politics or military intelligence, they're for players of the computer game Minecraft and another for fans of a Filipino YouTube celebrity.

The investigative website Bellingcat has seen evidence, external that some documents could have been posted in January or even earlier.

These documents remained on Discord largely undetected, before spreading to other social platforms in early April and eventually being picked up by US officials and the mainstream press.

Then, they started disappearing.

Read more about how secret files on Ukraine spread.

According to Attorney General Garland, Teixeira will make an initial court appearance at the US District Court in Massachusetts.

It is unclear when that court appearance will take place.

Garland said that more information on the investigation will be released at "the appropriate time".

Attorney General Merrick Garland is up now.

He confirms that the Justice Department arrested Jack Douglas Teixeira on Thursday for allegedly leaking highly sensitive US intelligence documents.

Image source, Reuters

The leak of highly sensitive secret files has whipped top political and military officials into high gear.

US President Joe Biden said earlier that investigators were close to finding the person who leaked the documents.

"There's a full blown investigation going on, as you know, with the intelligence community and the Justice Department, and they're getting close," Biden told reporters on Thursday from Ireland.

On Monday, national security spokesman John Kirby was cautious, telling reporters at the White House that the government will let the justice department "do their job, investigate this, see what they learn".

The same day, high-ranking Pentagon official Chris Meagher, while refraining from verifying any specific information, said the leak presents “a very serious risk to national security and have the potential to spread disinformation”.

A day later, Defence Secretary Lloyd Austin said the US will "turn over every rock until we find the source of this and the extent of it".

Image source, WBZ

The FBI has announced that it has "made an arrest and is continuing to conduct authorized law enforcement activity at a residence in North Dighton, Massachusetts".

Some US media outlets have reported that Teixiera is the person who has been arrested, but the BBC has yet to independently confirm this.

We'll likely get more clarity about that arrest in the next few minutes from Attorney General Merrick Garland, who is making a public statement.

Stay with us for more updates.

We're hearing from General Pat Ryder, who is giving a briefing at the Pentagon.

Gen Ryder says they are aware of press reports regarding a potential suspect, but because this is an ongoing investigation he cannot comment.

Due to the ongoing nature of the investigation, he refers those listening to his address to the Department of Justice and the information they can make available.

He adds that defence secretary Lloyd Austin has said the department is taking the issue very seriously.

He says that just because classified information has been posted publicly, that does not mean the information has now been de-classified, so he cannot address what's in the leaks.

Gen Ryder also says that confirming or denying any of the information would be compromising.

The suspect in the leak is named Jack Teixeira, US officials have told CBS News, the BBC’s US partner.

The New York Times earlier reported that the leader of an online gaming chat group where the files leaked in recent months had the same name, but they not identify Teixeira as the alleged leaker.

The Times has identified , externalTeixeira as being a 21-year-old member of the intelligence wing of the Massachusetts Air National Guard.

According to the newspaper and various other US media outlets, Teixera was the leader of an online gaming chat group. It was here that he is believed to have leaked the files.

On Wednesday, the Washington Post also published an interview, external with a member of the chat room where the documents initially appeared, who described the leaker as a young gun enthusiast in his early to mid-20s who works at a military base.

The FBI and other US officials have so far not commented publicly on Teixera.

Read more about what we know about the suspect here.

Image source, Reuters

General Pat Ryder is speaking to the media. You can watch live by clicking play at the top of the page.

Welcome to our live coverage.

If you’re just joining us, we’ve just learned from our US partner CBS News that Jack Teixeira is the man suspected of leaking highly sensitive US defence and intelligence documents.

The documents included sensitive information about the war in Ukraine, as well as on US allies and adversaries across the globe.

US defence officials have described the leak as a “very serious risk” to national security.

Stay with us for more updates on the leak and the search for the suspect.