Story highlights Taking such action would have tremendous ramifications and would likely be considered an act of war

Trump appeared to be referring to a series of close encounters between the US and Iran

Pensacola, Florida (CNN) Donald Trump vowed Friday that if Iran inappropriately approached US ships, they would be "shot out of the water."

"And by the way, with Iran, when they circle our beautiful destroyers with their little boats and they make gestures that our people -- that they shouldn't be allowed to make, they will be shot out of the water," he said at a rally here.

Taking such action would have tremendous ramifications and would likely be considered an act of war. The comments, even given Trump's penchant for tough language, are unusual for a presidential candidate.

Trump appeared to be referring to a series of close encounters between the US and Iran in international waters in the Persian Gulf.

An Iranian ship came within 100 yards of a US Navy patrol ship earlier this week in what the US Navy described as an "unsafe and unprofessional" action involving "harassing maneuvering."

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