The U.S. has launched an investigation into the leak of Pentagon documents revealing Israel’s preparations for an attack on Iran, according to CNN sources.

The documents, dated October 15-16, confirm that the Israeli Air Force conducted exercises and rehearsals for a potential strike, following Iran’s ballistic missile attack on October 1.

Leaked on Telegram, the documents discuss Israel’s military movements, including exercises with air-launched ballistic missiles and covert drone activity, Ynet News has reported.

U.S. agencies are now investigating who had access to the classified information, with the FBI involved. Some speculate the leak could have political motives.

Written by B.C. Begley