Israel set up a clandestine military outpost in the Iraqi desert to support its air campaign against Iran and launched airstrikes against Iraqi troops who nearly discovered it, the Wall Street Journal reports, citing people familiar with the matter, including US officials.

Israel built the installation, which housed special forces and served as a logistical hub for the Israeli air force, with the knowledge of the US just before the start of the US-Israeli war against Iran, the outlet said. It also included search-and-rescue teams positioned to assist any downed Israeli pilots, WSJ said.

Reuters could not independently verify the report. There was no immediate response from the Israeli prime minister’s office to a Reuters request for comment.

The base was almost discovered in early March after Iraqi state media said a local shepherd reported unusual military activity, including helicopter movements in the area.

Iraqi troops were dispatched to investigate, but Israeli forces used airstrikes to keep them at a distance and prevent the site from being discovered, the paper said, citing one of the sources.