A small U.S. Coast Guard boat fired a single shot toward an armed Iranian-flagged ship in the Persian Gulf during a brief encounter on Tuesday, a potentially provocative incident in a volatile area.

U.S. officials emphasized that the situation didn't escalate and that both vessels ended contact after the warning shot was fired.

The Coast Guard Patrol Boat Monomoy, working in the Persian Gulf, had been in contact with the bridge of the Iranian dhow, a traditional vessel common in the Middle East, when the Iranian crew abruptly broke off the conversation, U.S. defense officials said.

The Coast Guard dispatched a small boat from the Monomoy to investigate, said Navy Commander Kevin Stephens, a spokesman for the U.S. Fifth Fleet.

Cmdr. Stevens said the crew of the dhow aimed a .50 caliber machine gun at the Coast Guard boat, demonstrating "hostile intent." In response, the small Coast Guard boat fired a single shot. The incident occurred around 11:30 a.m. local time, Cmdr. Stevens said.

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