US Defense Secretary Lloyd Austin said on Tuesday United States It will continue to investigate the alleged leak of classified documents until its source is known.

The documents, classified as “classified” and “top secret,” first appeared on social media in March and reveal what details the military capabilities of some U.S. allies and adversaries.

“We will continue to investigate, turning every stone unturned, until we know the source and extent of this (leak),” Austin told a news conference at the State Department.

Austin, the first senior US official to comment on the leak, said the Defense Department knew the documents were released between February 28 and March 1, but did not know if the documents were posted online before those dates. .

“We will find these out as the investigation continues,” he said.

Later in a speech at Rice University in Texas, CIA Director William Burns said the leaks were “extremely unfortunate” but contained no details of what he described as a “very serious” investigation by the CIA, Defense and Justice ministries.

And, “we should also learn from it on the way to tighten our procedures.”

Investigators are working to identify a person or group with the ability and intent to release investigative reports. It may be the most leaked US government information since WikiLeaks released thousands of documents in 2013.

The documents contain some very important information, and they say they relate to the capabilities and shortcomings of the Ukrainian military, and one of the documents refers to the limited number of Western special forces in the country.

The US Department of Justice launched a criminal investigation that revealed the documents.

Some national security experts and U.S. officials suspect the source of the leak may be American, based on the various titles in the documents. They added that new perspectives may emerge as the investigation progresses.

France 24/Reuters