It's time for the United States to hold Iran accountable.

The USS Mahan, a U.S. Navy destroyer nicknamed "built to fight," fired three warning shots Sunday toward four Iranian vessels in the Strait of Hormuz, a politically strategic and often disputed strait between the Gulf of Oman and the Persian Gulf. The incident was spurred after the four Islamic Revolutionary Guard Corps ships sped toward the Navy warship, seemingly out of nowhere, while failing to respond to U.S. officials repeated requests for them to slow down, Reuters reported Monday morning.

The USS Mahan fired its three warning shots toward the Iranian vessels after the four ships came within 900 yards. The Navy was attempting to make contact with the Iranian vessels after they began encroaching on the U.S. warship at an atypical rate, Reuters reported. Iran’s Islamic Revolutionary Guard Corps responded to the Navy’s radio communication, but would not adhere to requests for the vessels to stop speeding toward the destroyer. A U.S. Navy helicopter responded by dropping a smoke float as the USS Mahan began firing warning flares, all while the four ships reportedly continued asking questions to U.S. officials.

As of Monday morning, it remained unclear exactly what communication transpired between the two nation’s vessels before the USS Mahan fired three warning shots toward Iran’s ships. Multiple officials spoke on conditions on anonymity, noting the U.S. destroyer was escorting two other U.S. military ships at the time of the incident, Reuters reported. 

The news arrived as the future of U.S.-Iranian relations remain unclear, with Iran recently warning President-elect Donald Trump not to toss the nuclear deal President Barack Obama’s White House administration spearheaded in 2015.

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