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Likely oil slicks in Strait of Hormuz after US tanker strikes: experts

Agence France-Presse
Agence France-Presse
Sep 10, 2026
Copernicus images indicated possible oil slicks after US strikes on tankers in the Strait of Hormuz
Copernicus images indicated possible oil slicks after US strikes on tankers in the Strait of Hormuz — -

Recent satellite images analysed on Thursday appear to show oil slicks near the Strait of Hormuz, after US strikes on tankers suspected of links to Iran's Revolutionary Guard.

An image from the European Copernicus programme taken on Wednesday shows brownish streaks on the surface of the water some 20 kilometres (nearly 12.5 miles) off the Iranian coast, to the east of the strait.

Another Copernicus image of the same location taken on Thursday shows winding streaks of a similar length.

Several researchers and experts told AFP they were most likely oil slicks, in an area near coral reefs listed under the Ramsar Convention as wetlands of international importance.

Satellite images alone are not enough to determine the presence of hydrocarbons with certainty nor their precise origin.

But Vincent Kerbaol, head of satellite maritime surveillance operations at the French company CLS, said they were "strong indications" of "pollution probably left by ships".

Leon Moreland, a researcher at the UK-based Conflict and Environment Observatory NGO, also said the images were "highly likely oil slicks, owing to their visual appearance, morphology/spread and absence of evidence for phytoplankton/algal blooms".

SkyTruth, a US non-profit that conducts environmental surveillance, equally came to the same conclusion.

Kerbaol said that if they were fuels with "a certain volatility", the slicks "could evaporate in three to four days, unlike crude oil, which is more long-lasting.

Two of the detected tracks start exactly where the tankers Riesco and Kylo transmitted their last signals before being sunk on September 8 and 5 respectively.

The US military announced that it had destroyed five tankers in the Gulf of Oman on Tuesday in response to ballistic missile attacks by Iran's Revolutionary Guards against a US warship.

The 240-metre-long Riesco sank after catching fire, according to images published by the US military on X.

"Based on the location and timing, Riesco seems like a probable candidate," said Moreland.

The last available signal from the vessel on the MarineTraffic site dates from 2200 GMT on Tuesday, precisely at one end of the slick closest to the coast.

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