The intelligence report, circulated across the US military this spring during the war with Iran, set off alarm bells: a Chinese ship in the Middle East was transporting components of a nuclear weapons program. The US military swung into action with plans to intercept the vessel, according to four sources. Armed members were preparing to board the ship, and military planes were in the air, two sources said.

Just before the planned operation, officials dug deeper and found the report—put together by a special operations command analyst—had been generated with AI. A chatbot the analyst used inaccurately identified the material the ship was carrying. CNN was not able to learn what the misidentified cargo was.

The report was "entirely false," one source said, but it also "almost started a war." Any US operation against a Chinese vessel could have risked spiraling into an armed conflict. Across the US military and intelligence community, officials are pushing to weave AI into nearly every facet of their work. But the episode underscores the profound risks of using this powerful, new and relatively poorly understood technology for targeting in the middle of a war.