The patrol boat United States Coast Guard Cutter Maui navigates through the Arabian Gulf on Jan. 24, 2019. (Photo credit: U.S. Naval Forces Central Command)

The Iranian boats approached the U.S. formation at high speed, closing in as close as 150 yards, and the U.S. Coast Guard Cutter Maui fired about 30 warning shots from a machine gun before the Iranian boats left, the Pentagon said.

WASHINGTON, May 10 -- The Pentagon said on Monday that a U.S. Coast Guard ship fired warning shots during a close encounter with Iranian Islamic Revolutionary Guard Corps Navy (IRGCN) fast boats in the Strait of Hormuz earlier in the day.

Pentagon spokesman John Kirby said in a daily briefing that six U.S. Navy vessels escorting USS Georgia, a guided missile submarine, encountered 13 IRGCN fast attack boats while transiting the Strait of Hormuz.

He said the Iranian boats approached the U.S. formation at high speed, closing in as close as 150 yards (about 137 meters), and the U.S. Coast Guard Cutter Maui fired about 30 warning shots from a machine gun before the Iranian boats left.