US military boards Iranian-flagged oil tanker suspected of breaching blockade

On 2026-05-20, the U.S. military boarded the Iranian-flagged commercial oil tanker M/T Celestial Sea in the Gulf of Oman and searched it after suspecting it was trying to violate the American blockade. U.S. Central Command said the vessel was redirected; the article described this as at least the fifth boarding since the blockade began. No fatalities were reported.