Malaysia says it has intercepted a large oil tanker that was involved in a collision with another ship before fleeing the scene and turning off its tracking system.

The coastguard says it has located and detained Ceres I, sailing under the flag of São Tomé and Príncipe, and two tugboats that were towing the vessel off the country’s eastern coast.

The ship had collided with the Singapore-flagged Hafnia Nile on Friday, causing both ships to catch fire.

Officials in Singapore say all crew members from both ships were rescued.

Malaysia’s coastguard said Ceres I had left the location immediately after the collision that caused a blaze and injured at least two crew members.

The incident happened about 55 km northeast of the Singaporean island of Pedra Branca, the Maritime and Port Authority of Singapore (MPA) said.

The head of Malaysian coast guard’s search and rescue team, Zin Azman Mohamad Yunus, has not explained why the São Tomé and Príncipe-flagged tanker tried to flee, but added that further investigations would be carried out.

The authorities in Singapore said after around 40 crew members were rescued from the blazing ships, around 26 of them remained on Ceres I to tackle the fire.

The Singapore-flagged Hafnia Nile, was reportedly carrying naphtha, a highly flammable type of petroleum.

The cause of the collision is still unclear. Singapore maritime authorities said ship traffic in the busy waterway was unaffected.

However, Malaysian coastguard officials found an oil spill covering around 17 square kilometres.

Ceres I is a large crude oil carrying supertanker. Some reports suggests it could be part of a so-called ‘dark fleet’, carrying oil from countries under sanctions.

A market intelligence service, S&P Global Commodities at Sea, says the ship, operated by China’s Shanghai Prosperity Ship Management, has previously carried Iranian crude, which is subject to US sanctions.