Ships sailing through the Strait of Hormuz and the Persian Gulf have been experiencing GPS interference and various other problems that US officials suspect is the work of the Iranians.
The Iranians had jammers aimed at disrupting the GPS navigation systems on ships and aircraft so that they might wander into Iranian waters or airspace, justifying a seizure.
The US Department of Transportation’s Maritime Administration has issued a new warning to commercial shipping about Iranian threats in the Strait of Hormuz and Persian Gulf, saying that some ships have reported having their GPS interfered with.
Additionally, the administration warned that there have been reports of “unknown entities falsely claiming to be US or coalition warships.”
Since May 2019, the following maritime incidents have occurred in this region.
- Six attacks against commercial vessels
- Shoot-down of U.S. Navy remotely piloted aircraft over international waters
- Attempted at-sea interdiction of Isle of Man-flagged M/V British Heritage (oil tanker)
- Seizure of ex-Panama-flagged M/V Riah (oil tanker)
- Seizure of U.K.-flagged M/V Stena Impero (oil/chemical tanker)
- Detention and subsequent release of Liberian-flagged M/V Mesdar (oil tanker)
US said that during “at least two” recent encounters involving Iranian military forces, vessels reported GPS interference.
One vessel reportedly shut off its Automatic Identification System (AIS) before it was seized, complicating response efforts.
Vessels have also reported spoofed bridge-to-bridge communications from unknown entities falsely claiming to be US or coalition warships, the warning added.
A US defense official told CNN that Iran has placed GPS jammers on Iran-controlled Abu Musa Island, which lies in the Persian Gulf close to the entrance of the Strait of Hormuz.
The official said that Iran had placed the jammers at that location in an attempt to disrupt civilian aircraft and ship navigation systems.
This is so that ships or planes will mistakenly wander into Iranian waters or airspace while their GPS systems were not functioning properly, giving Iranian forces the pretext needed to seize them.
The official said that Iranian military boats have been “spoofing” the automatic identification system merchant ships use to report and disguise their vessels as merchant ships instead of Islamic Revolutionary Guard Corps or Iranian Navy vessels.