A U.S. Navy destroyer fired three warning shots at four Iranian fast-attack vessels after they closed in at a high rate of speed near the Strait of Hormuz, two U.S. defense officials told Reuters on Monday.

The incident, which occurred Sunday and was first reported by Reuters, comes as U.S. President-elect Donald Trump prepares to take office on Jan. 20. In September, Trump vowed that any Iranian vessels that harass the U.S. Navy in the Gulf would be "shot out of the water."

USS Mahan established radio communication with the Islamic Revolutionary Guard Corps boats but they did not respond to requests to slow down and continued asking the Mahan questions. The Navy destroyer fired warning flares and a U.S. Navy helicopter also dropped a smoke float before the warning shots were fired.

The Iranian vessels came within 800 meters of the Mahan, which was escorting two other U.S. military ships.

The official added that the warning shots fired on Sunday were just one of seven interactions the Mahan had with Iranian vessels over the weekend, but the others were judged to be safe.

Most recently in August, another U.S. Navy ship fired warning shots towards an Iranian fast-attack craft that approached two U.S. ships.

Source: Reuters