IRGC declares Strait of Hormuz "closed"; three tankers targeted in two days

In a statement published by the IRGC's official media on Saturday, 17 October 2026, the Islamic Revolutionary Guard Corps (IRGC) Navy declared the Strait of Hormuz "closed" and warned that any ship that disobeys the rules set by the force will face consequences. The announcement came a few hours after the IRGC's claim of an explosion on a supertanker in the Strait of Hormuz, which DIAR covered in its earlier report.

The IRGC claims the supertanker, which was carrying more than two million barrels of crude oil, was travelling on an "unauthorized" route, had switched off its tracking systems and radar, and suffered a "severe explosion" and fire after hitting a sea mine. The ship's name, flag and the condition of its crew have not been disclosed, and the exact location of the incident is also unclear. As of publication of this report, no independent maritime source has confirmed that the vessel hit a mine.

Three tankers targeted in two days

With this incident, the number of tankers targeted in the waters of the Persian Gulf and the Strait of Hormuz since Friday, 16 October, has risen to three. The United Kingdom Maritime Trade Operations (UKMTO) had earlier reported that a tanker about 68 nautical miles from Saudi Arabia's port of Jubail was targeted with RPG fire from a small boat, and that all of its crew are safe.

The new claim is the IRGC's fourth similar claim in eight days. On 14 October the IRGC claimed that a container ship had hit a mine and sunk; but US Central Command (CENTCOM) said that ship had been hit by an IRGC projectile, not a mine. The Joint Maritime Information Center (JMIC) has also confirmed 149 maritime incidents since 1 March, without any mine strike being recorded among them.

The US response to the IRGC's claim

Admiral Brad Cooper, the CENTCOM commander, said on Friday that US forces and regional partners are protecting ships and that the Strait of Hormuz remains open to trade. Before that he had also announced the passage of 400 commercial ships in one week. US President Donald Trump also says the US naval blockade has stopped all of the Islamic Republic's ships from passing.

The IRGC is declaring the Strait of Hormuz closed even though none of its claims about ships hitting mines has been confirmed by an independent source.

Background

After the US and Israeli strikes began in late February 2026, the Islamic Republic effectively disrupted passage through the Strait of Hormuz, and the United States responded by placing the Islamic Republic's ports under a naval blockade. Under normal conditions the Strait of Hormuz is the passage for about a quarter of the world's seaborne oil, and the daily number of ships passing through it has fallen from about 138 before the war to about 30.