The United Kingdom Maritime Trade Operations (UKMTO) says it has received a report of an incident some nine nautical miles (about 17km) east of the Omani coast.
“Military authorities have reported that a container ship has sustained damage to the rear of the vessel, which has caused a fire on board,” it said.
“Vessels are advised to transit with caution,” it added.
The alert came moments after CENTCOM announced the start of a third round of strikes on Iran, citing an Iranian attack on a Cyprus-flagged ship in the strait.