The leak of classified US documents, particularly those related to Ukraine and which appear to be mostly authentic, poses a “very serious” risk to the national security of the United States, the Pentagon assessed on Monday, reports AFP.

The fact that these documents are being distributed online poses a “very serious risk to national security and can fuel disinformation,” Chris Meagher, the assistant secretary of defense, told reporters.

According to him, the Pentagon is still working to determine the extent of the leaks of classified information that have occurred in recent weeks, writes CNN.

“The Department of Defense is working around the clock to review the scope and scale of the spill, the impact assessment and our mitigation measures,” Meagher said.

“We are still investigating how it happened and the extent of the problem. Steps have been taken to look more closely at how this type of information is shared and to whom. We’re also still trying to assess what might be there.”

In recent days, a steady stream of photos of classified documents have been revealed on Twitter, Telegram, Discord and other sites, although some may have circulated online for weeks before gaining media attention.

A Pentagon spokesman declined to comment on their authenticity, saying a department team was working to determine whether they were real, but noted that the released photos contained confidential information.

“The photos appear to show documents in a format similar to that used to provide daily updates for our operations related to Ukraine and Russia, as well as other intelligence updates,” he said, but some “appear to have been redacted “.

At least one of the documents appears to have been altered to suggest that Ukraine suffered more casualties than Russia, even though the original allegedly says otherwise.

Meagher said Defense Secretary Lloyd Austin was first informed of the leak on April 6, and the next day he began “summoning senior executives on a daily basis.”

Last weekend, U.S. officials recognized allies and partners, some of whom were also involved in the leak, Meagher said.

The Pentagon team is also working to determine the scope of the leaked documents with classified material, which includes Defense Department legislative, public relations, policy, and legal advice, Meagher said.

Declassified U.S. military documents dating back several months were recently released on social media, providing a partial picture of the war in Ukraine, three U.S. officials told Reuters on Friday, adding that Russia or pro-Russian elements were likely behind the leak.

However, several US experts and officials believe there is a possibility that the source is someone from the US.

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