US Navy fire warning shots at Iran boat

The incident happened on Tuesday and involved the USS Thunderbolt, a Cyclone-class patrol ship involved in an exercise with American and other vessels in the Gulf.

The official said the Iranian naval vessel came within 140 metres of the Thunderbolt. The official said the Iranian vessel did not respond to radio calls, flares and warning sirens, forcing US sailors to fire the warning shots.

The Navy fired warning shots into the water over concerns about the possibility of a collision, CNN reported.

The Iranian ship, reportedly operated by the Iranian Revolutionary Guard Corps, then ceased its provocative actions but lingered in the area for some hours, a US official told CNN.

Iranian authorities did not immediately report the incident.

The American defence official spoke on condition of anonymity as the incident had yet to be made public. Iran and the US frequently have tense naval encounters in the Persian Gulf.