Threats to US ships in the Strait of Hormuz heard at the end of a Pentagon-released recording of an incident between Iranian patrol boats and US Navy warships last week may have been the work of a local heckler known as the "Filipino Monkey", The Navy Times has reported.

This has led several Navy experts to raise the possibility that a heckler, known locally as the "Filipino Monkey" - or a copycat - could have made the threats.

"Filipino Monkey" is believed to be more than one person. Its modus operandi is to listen in to ship-to-ship radio traffic before jumping in with insults and threats.