Warning on GPS jamming/spoofing in Strait of Hormuz

The US Department of Transportation’s Maritime Administration has warned shipowners and charterers that Iran could be engaged in interfering with ships’ GPS systems as they transit the Strait of Hormuz and elsewhere near Iran’s coast.

The Department said that merchant ships had reported “spoofed bridge-to-bridge communications from unknown entities falsely claiming to be US or coalition warships.”

US Central Command (CENTCOM) said in an email that “due to the heightened regional tensions, the potential for miscalculation or misidentification could lead to aggressive actions against vessels belonging to US, allied and coalition partners operating in the Arabian Gulf, Strait of Hormuz, and Gulf of Oman”. It said that a number of ships had reported a jamming of communications in recent weeks.

A US official told CNN that Iranian Navy and Islamic Revolutionary Guard Corps vessels have spoofed merchant ship automatic identification systems to make themselves look like commercial shipping vessels.

The US believes Iran has GPS jammers operating on Abu Musa Island in the Persian Gulf, with the intention of getting international ships and aircraft to wander accidentally into Iranian waters or airspace.

UK intelligence services have said that Iran might well have used Russian GPS spoofing technology to send the UK-flagged Stena Impero off course and into Iranian waters.