US forces boarded an Iranian tanker in the Gulf of Oman that was suspected of attempting to run the blockade.

Earlier today in the Gulf of Oman, U.S. Marines from the 31st Marine Expeditionary Unit boarded M/T Celestial Sea, an Iranian-flagged commercial oil tanker suspected of attempting to violate the US blockade,” US Central Command wrote on X Wednesday. “American forces released the vessel after searching and directing the ship’s crew to alter course.”

Earlier today in the Gulf of Oman, U.S. Marines from the 31st Marine Expeditionary Unit boarded M/T Celestial Sea, an Iranian-flagged commercial oil tanker suspected of attempting to violate the U.S. blockade by transiting toward an Iranian port. American forces released the… pic.twitter.com/1AVT0MudKY

— U.S. Central Command (@CENTCOM) May 20, 2026

Last month, Pakistan brokered a ceasefire between the US and Iran that was intended to reopen the Strait of Hormuz. Shortly after Tehran said it would allow commercial ships to transit the Strait, President Donald Trump announced a blockade of Iranian ports. In response, Iran reclosed the Strait of Hormuz.

CENTCOM reports it has stopped 91 ships attempting to reach or leave Iranian ports. Shipping analytics show dozens of Iranian vessels have successfully broken the blockade. Trump believes the blockade will result in intense economic suffering in Iran and force Tehran to comply with his demands.

The Strait, which was an open waterway before the conflict, has become a major issue in negotiations to end the war. Washington is demanding that Tehran allow ships to transit the Strait freely.

Tehran says that the Strait is now Iranian territory. Iran plans to charge tolls to ships transiting the waterway after the conflict ends.