US doubts over Iran boat 'threat'
BBC News, Thursday, 10 January 2008, 20:49 GMT

Iran has described the incident as an "ordinary occurrence"

An alleged threat to blow up US warships "may not have come" from Iranian speedboats involved in a recent stand-off, the BBC has learned.
The voice on a Pentagon tape could instead have come from another ship in the area or a transmitter on land, senior US Navy sources told the BBC.
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On a side note, a Brit working with the Omani navy/coastguard once told me that smugglers use swarming tactics too, overwhelming local patrols by making simultaneous runs with dozens of high speed boats (I'm not suggesting any connection whatsoever--just an interesting Straits of Hormuz tidbit!)