DUBAI, United Arab Emirates (AP) — The US Navy said Monday that its sailors and the United Kingdom Royal Navy had come to the aid of a ship in the crucial Strait of Hormuz after Iran’s Revolutionary Guard “harassed” it.

Three fast-attack Guard vessels with armed troops aboard approached the unidentified merchant ship at a close distance Sunday afternoon, the US Navy said in a statement. It offered black-and-white images it said came from a US Navy Boeing P-8 Poseidon overhead, which showed three small ships close to the commercial ship.