Who leaked secret Pentagon documents on Ukraine war? Biden says US 'close' to finding out.

DUBLIN – President Joe Biden said Thursday that U.S. officials are “getting close” to wrapping up their investigation into the leak of highly classified documents about the war in Ukraine and U.S. spying.

Biden told reporters traveling with him in Ireland, where he is on a three-day trip, that he could not provide an update on the case because “there’s a full-blown investigation going on” involving the intelligence community and the Justice Department.

“They’re getting close,” he said.

Asked by USA TODAY if he was concerned about the leak, Biden said, “I'm not concerned about the leak. I'm concerned that it happened. But there's nothing contemporaneous that I'm aware of that’s of great consequence.”

The leader of an online group where a trove of documents were shared, Jack Teixeira, a member of the Massachusetts Air National Guard, has drawn the scrutiny of law enforcement officials, a person familiar with the inquiry said Thursday.

Law enforcement officials are interested in speaking with Teixeira, whose group has a shared interest in guns. But his status in the fast-moving investigation was not immediately clear.

Teixeira's link to the investigation was first disclosed by the New York Times.

Dig deeper: Pentagon document leak: Here are the biggest takeaways after U.S. military secrets leaked

More: Pentagon warns that leak of secret documents on Ukraine war could lead to loss of lives

The documents, which have appeared on social media, seem to show printouts of battlefield updates and assessments. Some are labeled top secret, and not to be shared with even allies.

The secrets exposed in the leak appear to include the shortage of critically needed artillery shells for Ukrainian forces ahead of an expected spring offensive, U.S. spy planes in the region and information revealing the extent of U.S. spying on its adversaries and allies.

The documents appear to have been used to update senior officials, including the Joint Chiefs of Staff on the war in Ukraine that Russian President Vladmir Putin launched in February 2022

The Justice Department has begun a criminal investigation at the Pentagon's behest.

Who is behind the leak of classified documents?

The Times said Teixeira, the Air National Guardsman national guardsman who investigators are looking to talk to, oversaw a private online group named Thug Shaker Central, where about 20 to 30 people, mostly young men and teenagers, came together over a shared love of guns, racist online memes and video games. The documents were posted in the group chat.

It wasn't immediately clear if a young Air National Guardsman in Teixeira's position could have had access to such highly sensitive briefings, the paper said. Officials within the U.S. government with security clearance often receive such documents through daily emails, one official told The Times, and those emails might then be automatically forwarded to other people.

The Washington Post said messages posted in the group appeared to be near-verbatim transcripts of classified intelligence documents that a young man, nicknamed "OG," indicated he had brought home from his job on a “military base.”

The Times identified OG as Teixeira.

OG claimed he spent at least some of his day inside a secure facility that prohibited cellphones and other electronic devices, which could be used to document the secret information housed on government computer networks or spooling out from printers, the Post said.

He annotated some of the hand-typed documents, according to a member of the group interviewed by the Post, translating arcane intel-speak for the uninitiated, such as explaining that “NOFORN” meant the information in the document was so sensitive it must not be shared with foreign nationals.

Later, rather than spend his time copying documents by keyboard, he took photographs of the genuine articles and dropped them in the server, the Post said.

Joey Garrison and Michael Collins cover the White House. Follow Garrison on Twitter @joeygarrison and Collins @mcollinsNEWS.

This article originally appeared on USA TODAY: Biden in Ireland: US 'close' to ending leaked Pentagon documents probe