An oil tanker that left the site of a collision and fire east of Singapore has been intercepted off the coast of Malaysia in the early hours of July 21, Malaysian maritime authorities said.

Ceres I, a crude oil tanker sailing under the flag of Sao Tome & Principe, and the Hafnia Nile, a Singapore-flagged refined-products tanker, crashed early in the morning of July 19, in one of the world’s busiest waterways, setting both ablaze. Ceres I appears to have then switched off its transponder for more than a day, according to Bloomberg ship-tracking data.

After being tracked by Malaysian authorities, Ceres I was intercepted 28 nautical miles off Tioman Island at 1:20 a.m. local time July 21, pulled by two tugboats, the coast guard said in a statement. All three have been detained. 

An aerial survey detected some traces of a spill, but further checks and an investigation will follow.

Ceres I was built in 2001, according to data compiled by Bloomberg, meaning it’s still in use well beyond when most owners would consider scrapping a vessel. It was also sailing under an obscure flag, used by only 55 vessels out of a merchant fleet of tens of thousands of ships — both characteristics common to almost all “dark fleet” ships.

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The vessel, a very large crude carrier or VLCC, hauled cargoes from Iran and Venezuela earlier in 2024 and in 2023, according to data from market intelligence firm Kpler. 

The exact cause of July 19’s crash remains unclear.