New Batch of Classified Documents Appears on Social Media Sites

WASHINGTON — A new batch of classified documents that appear to detail American national security secrets from Ukraine to the Middle East to China surfaced on social media sites on Friday, alarming the Pentagon and adding turmoil to a situation that seemed to have caught the Biden administration off guard.

The scale of the leak — analysts say more than 100 documents may have been obtained — along with the sensitivity of the documents themselves, could be hugely damaging, U.S. officials said. A senior intelligence official called the leak “a nightmare for the Five Eyes,” in a reference to the United States, Britain, Australia, New Zealand and Canada, the so-called Five Eyes nations that broadly share intelligence.

The latest documents were found on Twitter and other sites on Friday, a day after senior Biden administration officials said they were investigating a potential leak of classified Ukrainian war plans, include an alarming assessment of Ukraine’s faltering air defense capabilities. One slide, dated Feb. 23, is labeled “Secret/NoForn,” meaning it was not meant to be shared with foreign countries.

The Justice Department said it had opened an investigation into the leaks and was in communication with the Defense Department but declined to comment further.

Mick Mulroy, a former senior Pentagon official, said the leak of the classified documents represents “a significant breach in security” that could hinder Ukrainian military planning. “As many of these were pictures of documents, it appears that it was a deliberate leak done by someone that wished to damage the Ukraine, U.S., and NATO efforts,” he said.

One analyst described what has emerged so far as the “tip of the iceberg.”

Early Friday, senior national security officials dealing with the initial leak, which was first reported by The New York Times, said a new worry had arisen: Was that information the only intelligence that was leaked?

By Friday afternoon, they had their answer. Even as officials at the Pentagon and national security agencies were investigating the source of documents that had appeared on Twitter and on Telegram, another surfaced on 4chan, an anonymous, fringe message board. The 4chan document is a map that purports to show the status of the war in the eastern Ukrainian city of Bakhmut, the scene of a fierce, monthslong battle.

But the leaked documents appear to go well beyond highly classified material on Ukraine war plans. Security analysts who have reviewed the documents tumbling onto social media sites say the increasing trove also includes sensitive briefing slides on China, the Indo-Pacific military theater, the Middle East and terrorism.