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The most mysterious aspect of a recent naval confrontation between the U.S. and Iran was a voice. Over the radio, an ominous voice with a strange accent threatened American ships. The Navy is investigating, but sailors who know the Persian Gulf well say they've heard that voice many times. Radio pranksters are commonplace in the Gulf, and they've picked up an odd nickname, the Filipino Monkey.
From Abu Dhabi, NPR's Ivan Watson reports.
IVAN WATSON: On January 6th, five Iranian navy speedboats approached a convoy of three U.S. Navy warships sailing through the busy Strait of Hormuz. An officer from Iran's Islamic Revolutionary Guard Corps says they were conducting a routine maritime inspection procedure, but Commander Lydia Robertson, a spokesperson for the U.S. Navy's 5th Fleet stationed in the Gulf, disagrees.
Commander LYDIA ROBERTSON (Spokesperson, 5th Fleet, U.S. Navy): These boats approached the three ships very fast, they maneuvered very aggressively. There was a threatening radio transmission that came to the ships over the channel 16, which is the normal line for communication between mariners.
(Soundbite of radio transmission)
Unidentified Man #1: I am coming to you.
WATSON: The Pentagon released this video of the incident during which an accented English speaker can be heard, apparently warning the U.S. Navy ship that it will explode.
(Soundbite of radio transmission)
Unidentified Man #1: You will explode after a few minutes.
Unidentified Man #2: You will explode after a few minutes.
WATSON: Commander Robertson says there are several possible sources for the ominous radio transmission.
Cdr. ROBERTSON: It ranges from a possible heckler to maybe the transmission came from a shore station, maybe from a passing ship.
WATSON: In fact, hecklers have long plagued the open, international radio channel used for ship-to-ship communication in the Persian Gulf.
Mr. JOHN HUSCHON(ph): Over the radio in channel 16 of the VHF, these voices used to come across, saying Filipino Monkey.
WATSON: John Huschon is a Dubai-based veteran of the British Merchant Marine. He says radio hecklers in the Gulf quickly earned themselves the nickname Filipino Monkey.
Mr. HUSCHON: They would just come on in a highly - a high-pitched voice, would sort of scream out the term Filipino Monkey. And sometimes, when they stop, somebody else would pick it up, and it was a real nuisance.
WATSON: American sailors say to this day, the Filipino Monkey is a recurring phenomenon in the Gulf.
Mr. MICHAEL BURNS (Civilian Mariner, Massachusetts): They just kind of chatter on the radio incessantly, and try to, I guess, provoke a reaction from other people listening to the radio or generally kind of harass other mariners that might be of that nationality.
WATSON: Michael Burns is civilian mariner based in Massachusetts. He has sailed repeatedly through the Strait of Hormuz aboard ships contracted by the U.S. government.
Mr. BURNS: I have heard derogatory remarks made about the U.S. Navy while in that area or rival fishermen or, really, whatever happens to strike their particular source of amusement at that moment.
WATSON: Veteran mariners assume that the hecklers are bored sailors playing on their ship radios. But the U.S. Navy says the timing of the radio message on January 6th was extremely suspicious.
In the aftermath of the incident, President Bush warned Iran there would be serious consequences if Iranian forces attack U.S. warships. Tehran says Washington is exaggerating the incident for political gain.
Ivan Watson, NPR News, Abu Dhabi.