DUBAI, United Arab Emirates (AP) — The U.S. Navy says Iran has threatened two American maritime patrol aircraft flying over the Strait of Hormuz.

It's the latest in a series of encounters between Iranian and American forces raising tensions in and around the Persian Gulf.

U.S. 5th Fleet spokesman Cmdr. Bill Urban said in a statement Tuesday the aircraft were flying in international airspace on Saturday when Iranian air defense stations warned them that they were nearing Iranian airspace.

He says the Iranians said "we will fire Iranian missile" if they did not change course, and that the Americans replied they were conducting routine operations in international airspace. He says the planes then continued on their mission.

Urban called the interaction "unprofessional," but not "unsafe," because the planes were out of known surface-to-air weapons range.