A U.S. Navy video and several photos show Iranian vessels harassing U.S. Coast Guard ships in the Persian Gulf earlier this month, the first such incident in almost a year.

Three Iranian Islamic Revolutionary Guard Corps Navy (IRGCN) fast-attack boats and one larger support vessel, Harth 55, swarmed U.S. Coast Guard patrol boats Wrangell and Monomoy during maritime security operations in international waters on April 2.

The U.S. Navy says that during the three-hour incident, the Harth 55 “repeatedly crossed the bows of the U.S. vessels at an unnecessarily close range,” at one point coming within 70 yards of the U.S. ships.

One “unsafe and unprofessional” approach, as the Navy described it, was captured on video.