FBI investigating leak of US intel on Israel's attack plans for Iran

The FBI has opened an investigation into the unauthorized leak of classified U.S. intelligence documents containing Israel’s potential plans for a retaliatory strike against Iran, the bureau said Tuesday.

"The FBI is investigating the alleged leak of classified documents and working closely with our partners in the Department of Defense and Intelligence Community,” the FBI said in a statement.

The bureau declined to offer further details, citing an ongoing investigation. The Pentagon did not immediately return a request for comment as to its role in the investigation.

Multiple news outlets reported over the weekend that the U.S. intelligence material, marked top secret and attributed to the National Geospatial-Intelligence Agency and National Security Agency, were posted to the Telegram messaging app Friday. The Telegram channel associated with the leak identifies as being based in Tehran, The Associated Press reported.

The material in question includes a pair of documents that indicate Israeli military exercises to prepare for an attack on Iran and another that suggest preparations for an Iranian counterattack.

The world has been bracing for an Israeli retaliatory strike on Iran since Tehran fired some 180 ballistic missiles at Israel on Oct. 1 in response for the killings of Hamas leader Ismail Haniyeh in Tehran in July and Hezbollah chief Hasan Nasrallah in Beirut in September.

White House national security spokesperson John Kirby told reporters Monday that a Pentagon investigation is seeking to determine whether the documents were a hack or a leak, but this is the first time the FBI has acknowledged it is also involved in the probe.

"We're not exactly sure how these documents found their way into the public domain," Kirby said, calling it "unacceptable."

Kirby added that President Biden is “deeply concerned” about the breach.