Editor's Note: This article originally appeared on Business Insider.

President Donald Trump said Wednesday that he has ordered the Navy to “destroy” any Iranian gunboat that harasses U.S. ships.

No additional clarity or guidance on the instructions purportedly delivered to the Navy have been provided.

The president's announcement follows an incident last week in which a swarm of nearly a dozen Iranian gunboats sailed out to harass U.S. Navy and Coast Guard vessels operating in the Persian Gulf.

U.S. Naval Forces Central Command said last Wednesday that 11 Iranian Islamic Revolutionary Guard Corps Navy boats “conducted dangerous and harassing approaches,” repeatedly crossing the bows and sterns of the US ships — at one point closing within 10 yards of one of the Coast Guard cutters.

The U.S. military said that the U.S. vessels issued multiple warnings over bridge-to-bridge radio and sounded their horns, but the Iranian boats did not respond for about an hour.

After finally responding, the Iranian vessels moved away from the American ships.

“The IRGCN's dangerous and provocative actions increased the risk of miscalculation and collision,” U.S. Naval Forces Central Command said in a statement.

Iran photo

At the time of the incident, the Navy expeditionary mobile base vessel USS Lewis B. Puller, destroyer USS Paul Hamilton, and patrol ships USS Firebolt and USS Sirocco, together with the Coast Guard cutters USCGC Wrangell and USCGC Maui, were carrying out joint operations with Army AH-64E Apache attack helicopters in the Persian Gulf.

The U.S. military has been experimenting with having Army helicopters take off from Navy ships to “enhance the capabilities of U.S. forces to respond to surface threats,” such as the gunboats Iran routinely sends out to harass both military and commercial vessels.

In its statement following last week's run-in with Iranian forces, U.S. Naval Forces Central Command concluded by saying that “U.S. naval forces continue to remain vigilant and are trained to act in a professional manner, while our commanding officers retain the inherent right to act in self-defense.”

Insider reached out the Navy and U.S. Central Command for comment but was redirected to the White House, which did not comment on the president's tweet.

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