The documents are attributed to the US Geospatial Intelligence Agency and the National Security Agency, the reports said.

The investigation by US officials will assess who had access to the documents and whether it was a deliberate leak or if they had been hacked, the reports said.

One of the documents states that the Israeli Air Force continues to prepare for an attack on Iran and is conducting “a second major employment exercise,” the reports said. The air force is “likely to conduct air-to-air refueling and search and rescue operations with a large number of aircraft,” the reports said.

The other document details how the Israeli military continues to prepare munitions “certainly for an attack on Iran,” the reports said.

The documents appeared on the Telegram channel Middle East Spectator, which is described as pro-Iranian, and the linked X account shows it to be in Iran.

In a written statement, Middle East Spectator said that “the documents first appeared in a private Telegram group,” before receiving them in a private message.

It was unclear what impact the leak might have on Israeli military planning for a possible attack on Iran, or on Israeli-American relations.