Iran's IRGC says in the early hours of today, two offending tankers were hit and stopped, and 4 offending tankers quickly changed course

Tanker interdictions and strikes attributed to the IRGC follow a well-worn pattern in the Gulf: episodic harassment or seizure of vessels described as offending, usually framed by Tehran as enforcement against sanctions evasion or smuggling rather than escalation, with the frequency of incidents tending to track the state of nuclear and sanctions diplomacy. The transmission channel to crude is concrete: not lost supply in the first instance, but the war-risk premium on freight and insurance for Gulf transits, and any widening of the risk zone around the Strait of Hormuz, through which a large share of seaborne crude passes. The distinction that has historically mattered is between harassment that leaves shipping flowing, which has tended to fade from pricing within sessions, and incidents involving casualties, mined hulls, or a declared closure threat, which have held the premium. On previous occasions of this kind the follow-ons have been statements from the US naval presence in the region, advisories to flag states and owners, and any change in vessel routing behaviour visible in tracking data. The claims are one-sided and unverified at this stage; confirmation from independent maritime security sources and the identity and flags of the tankers are the first things that clarify severity. Retaliation rhetoric from either side, rather than the interdictions themselves, has typically been the tell for whether an episode extends.