The United States has launched an investigation into the leak of two confidential intelligence reports detailing Israel’s preparations for a counter-attack on Iran, according to House Speaker Mike Johnson, R-La., on Sunday.

The leaked documents are believed to have been generated by the National Geospatial-Intelligence Agency, outlining U.S. assessments of Israeli Air Force and Navy strategies, based on satellite data collected on October 15-16.

These documents started appearing on the Telegram messaging platform last week. Israel has been organizing a response to a missile attack executed by Iran on October 1, marking the second such assault in six months. In the aftermath, Israel has ramped up its military activities in Gaza and Lebanon, particularly following the elimination of Hamas leader Yahya Sinwar.

During a CNN interview, Johnson confirmed that an “investigation (is) underway and I will receive a briefing shortly.”

“We are closely monitoring the situation,” Johnson further noted.

Both the National Geospatial-Intelligence Agency and the Office of the Director of National Intelligence did not respond promptly to requests for statements. The Pentagon has indicated it is also investigating the reports of the leak.

The New York Times mentioned that officials have privately acknowledged the authenticity of the documents, but noted that they likely only reflect a part of the information the U.S. possesses regarding the plans of its close ally.

The first document is labeled: “Israel: Air Force Continues Preparations for Strike on Iran and Conducts a Second Large-Force Employment Exercise,” detailing operations such as the management of ballistic and air-to-surface missiles.

The second document is titled: “Israel: Defense Forces Continue Key Munitions Preparations and Covert UAV Activity Almost Certainly for a Strike on Iran.” UAVs refer to unmanned aerial vehicles, commonly known as drones.

President Joe Biden addressed reporters last week, stating he has a clear understanding of when and how Israel might launch an attack against Iran. He also pointed out a potential opportunity to resolve the ongoing conflict between the two adversaries.