About 50 members of the United States military’s Joint Staff have reportedly undergone lie-detector tests as authorities investigate the leaking of classified information to journalists.

The polygraph examinations were reportedly conducted in August and involved military officers and civilian workers suspected of disclosing sensitive details. Among the information leaked were reports concerning shortages in US weapons stockpiles following the war with Iran.

Several media reports have raised concerns about depleted supplies of important munitions, including long-range missiles and Patriot air-defence interceptors.

The Joint Staff, which has an estimated 1,500 to 2,000 personnel, is responsible for helping coordinate military operations, defence policies and war planning with US combatant commands around the world.

The reported scale of the investigation is unusual, particularly because it involves personnel at relatively senior levels. Retired Rear Admiral Donald Guter, who previously served as the Navy’s top judge advocate general, said he had never seen polygraph examinations conducted so extensively among senior military personnel.

Pentagon spokesman Sean Parnell confirmed that the Department of Defence investigates unauthorised disclosures involving classified national security information but declined to provide details about the current investigation.

He said protecting classified information was essential to the security of the United States and American troops deployed around the world.

The leak investigation comes as the Pentagon faces growing scrutiny over reports concerning US military readiness and weapons supplies during the conflict with Iran.

President Donald Trump has repeatedly called for stronger action against those responsible for unauthorised disclosures. He has also attacked some reports about the war and the military’s preparedness, describing certain leaks as “treasonous.”

It remains unclear whether the investigation has identified anyone responsible for the leaks or whether disciplinary action will follow the polygraph tests.