The US Navy’s 5th Fleet has followed up yesterday’s revelation to The Wall Street Journal of a 3-hour swarming incident by Islamic Revolutionary Guard Corps (IRGC) boats of American ships in the Persian Gulf earlier this month by releasing partial video of the dangerous Iranian maneuvers to the public.

The incident happened on April 2 but had never been disclosed before Monday. The WSJ described “U.S. Navy officials confirmed that three fast attack crafts and one ship known as Harth 55, a 180-foot, twin-hulled support vessel, swarmed the two Coast Guard ships while they were patrolling international waters in the southern portion of the Persian Gulf.”

The above video shows a close-call moment wherein the Harth vessel comes within less than 100 yards, nearly colliding with the US Coast Guard ship.

“The larger vessel repeatedly crossed in front of the bows of the two U.S. vessels, the Monomoy and the Wrangell, coming as close as 70 yards away, officials said,” the WSJ noted further. 

It was considered by the Pentagon to be a major incident (unlike the more frequent, minor exchange of “warnings” between rival military vessels in the region) given the IRGC boats encircled and “buzzed” the US vessels for up to three hours

The Harth 55 is perhaps the most distinctive somewhat recent addition to Iran’s Navy, considered a high-speed vessel capable of carrying a helicopter and up to 100 troops. As can be seen in the US Navy’s brief video clip, it is indeed highly maneuverable and quick given its large size.

Currently there’s speculation that the Pentagon never disclosed the incident when it happened in order not to negatively impact the Vienna nuclear talks. Likely the Iranian side kept mum on it for the same reason, while also thinking they can continue such actions without public condemnation out of Washington.