Oil prices climbed again on Friday after a tanker was struck by explosive devices in the Strait of Hormuz, the narrow waterway that carries a large share of the world's seaborne crude. Brent crude rose to about $117 a barrel in early trading, while US West Texas Intermediate moved above $103, as traders priced in a higher risk of disruption to Gulf supplies.

What happened to the tanker

The United Kingdom Maritime Trade Operations (UKMTO) said a tanker transiting outbound was reported on fire about 25 nautical miles north-east of Khasab, Oman. It later said a small boat had approached the vessel on its port side and attached two explosive devices to the hull above the waterline. The blasts started a fire in the engine room that temporarily disabled the ship, but the fire was extinguished, the crew was reported safe, and there was no environmental impact. The vessel then continued to its next port of call.

Why markets reacted

The identity of those behind the attack has not been established, and UKMTO did not name the vessel in its warning. Maritime security sources identified it to Reuters as the Panama-flagged tanker LOUISE 1, and described the incident as the first known successful limpet-mine strike in the waterway since the US-Iran conflict began in February. The attack came alongside continued Houthi strikes on Saudi targets, which have kept traders alert to wider supply risks.

What to watch next

Analysts quoted by Reuters said continued action around Hormuz, combined with doubts over a diplomatic breakthrough, was keeping prices elevated on expectations of escalation in the coming weeks. The Hormuz incident is a reminder of how quickly a single shipping attack can move global oil prices.