Western military authorities are investigating an incident reported early on Friday between a commercial ship and a small military boat in international waters between Saudi Arabia and Iran.
According to a notice issued by the UK Maritime Trade Operations (UKMTO), an unidentified vessel was approached by a military boat as it was sailing 86 nautical miles (99 km) north-east of the Saudi refinery of Ras Tanura.
Personnel on the “small military craft” flashed a green laser towards the bridge of the commercial ship, which UKMTO did not name.
The UKMTO did also not identify the military craft’s nationality. However, the context suggests it is Iranian.
“The small military craft keeps hailing [the] vessel to turn to port towards Iranian territorial waters,” the UKMTO said.
The notice did not contain any other details, apart from the reported time of the incident, which is said to have occurred at 03:00 GMT.
“Vessels are advised to transit with caution and report any suspicious activity,” the UMKTO said, adding that authorities are investigating the incident.
The Iranian military often intervenes in waters off the country to intercept and sometimes board commercial vessels underway in the region.
Iran does so in cases where it suspects ships are engaged in oil smuggling, or to hijack vessels it then uses as bargaining chips to help release Iranian-controlled ships and cargoes seized by the US and its allies.
It is unclear whether the incident is connected to Iranian naval exercises in the north of the Persian Gulf.
The UKMTO said on Friday in a separate notice that vessels underway in the area reported challenges over VHF radio, including demands to alter course.
“It is assessed that these are most likely part of Islamic Revolutionary Guard Corps (IRGC) large-scale exercises,” the UKMTO said.
The IRGC Navy separately confirmed on Friday it is holding an execise in the area. According to the Iran's state-run IRNA news agency, the 19th Great Prophet's Exercise involves vessels with a speed of up to 90 knots, capable of firing missiles and launchable mines.
