KUALA LUMPUR, July 20 — Malaysia's coast guard said today that one of the two large oil tankers involved in a collision that led to fires on both had left the location of the accident and was believed to have turned off its tracking system.

The coast guard said it was tracking the whereabouts of the Sao Tome and Principe-flagged tanker Ceres I, which was suspected to be within Malaysian waters.

The Ceres I was involved in a collision reported early on Friday with the Singapore-flagged tanker Hafnia Nile about 55km northeast of the Singaporean island of Pedra Branca, the Maritime and Port Authority of Singapore (MPA) said on Friday.

The 22 crew of the Hafnia Nile and the 40 on the Ceres I were all accounted for, the MPA had said, adding that 14 crew from Ceres I were evacuated by a Singapore Air Force helicopter while 26 of its crew were conducting fire-fighting operations onboard.

The Chinese owner of the Ceres I could not be reached for comment on Friday and Saturday.

A video posted by the Malaysian coast guard showed the charred Singapore-flagged tanker Hafnia Nile afloat in a video the coast guard said was taken on Saturday.

Hafnia, the operator of Hafnia Nile, said on Friday a tug was on scene to assist the ship, which was drifting toward open sea, with specialised tugs en route to join firefighting efforts.

Singapore is Asia's biggest oil-trading hub and the world's largest bunkering port. Its surrounding waters are vital trade waterways between Asia and Europe and the Middle East and among the busiest global sea lanes.

Singapore's MPA did not immediately respond to a request for comment on Saturday. — Reuters