CNN:

President Donald Trump tweeted Wednesday that he has instructed the US Navy to "shoot down and destroy any and all Iranian gunboats" that harass US ships.

"I have instructed the United States Navy to shoot down and destroy any and all Iranian gunboats if they harass our ships at sea," Trump wrote.
 
It's unclear if Trump's tweet amounts to a standing order, and whether Central Command, which oversees operations in the Middle East, would fire upon an Iranian boat. CNN has reached out to the Pentagon and White House for additional comment.
 
CNN reported last week that the US Navy released video that it says shows Iranian naval vessels repeatedly conducting "dangerous and harassing approaches" toward US Navy warships in the North Arabian Sea and claimed that one Iranian vessel came within 10 yards of colliding with a US ship.

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