US Navy fires warning flare at Iranian vessel in Persian Gulf The U.S. and Iran routinely have tense encounters of this nature.

 -- A U.S. guided-missile destroyer fired a flare in the direction of an Iranian Revolutionary Guard ship this week during an encounter in the Persian Gulf, a Navy official has confirmed to ABC News.

The "guided-missile destroyer USS Mahan (DDG 72) had an unprofessional interaction with an Islamic Revolutionary Guard Corps Navy (IRGCN) vessel while transiting the international waters of the Arabian Gulf, April 24," the Naval Forces Central Command spokesman said of the Monday encounter.

The Iranian ship came within 1,100 yards of the Mahan, closing the distance, despite the U.S. ship’s maneuvering to open the distance between the two vessels, the spokesman said.

The Mahan employed bridge-to-bridge radio in an effort to reach the Iranian ship, and issued warning messages prior to the firing of the flare, the spokesman said.

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