Dramatic video has been released showing the moment a container ship crashed into an oil tanker in the North Sea, sending a huge fireball into the air.
Container ship Solong struck the Stena Immaculate off the east coast of Yorkshire on Monday morning, sparking a huge blaze on the Stena - which only went out on Wednesday.
Crowley, the maritime company managing the Stena Immaculate, said there were "no visible signs of smoke or flame" after firefighting efforts.
The Maritime and Coastguard Agency (MCA) said on Wednesday that "small pockets of fire" continued to burn onboard the Solong.
A sailor from the container ship is missing and presumed dead.
Its 59-year-old Russian captain was arrested by Humberside Police on Tuesday on suspicion of gross negligence manslaughter.
US-based maritime news website gCaptain reported it was told by a US official at the White House that foul play had not been ruled out.
UK transport minister Mike Kane told MPs something went "terribly wrong" for the crash to happen but there was "no evidence" of foul play.
The Marine Accident Investigation Branch (MAIB) said it will lead the safety investigation into the incident.
A team of inspectors was immediately deployed, and inquiries have focused on gathering witness accounts and obtaining digital data, the MAIB said.
Solong frequently travelled between Grangemouth in Scotland and Rotterdam and regularly used the route it took on the day of the collision, a statement added.
"Thirty-six crew from both vessels were recovered but tragically one member of crew from Solong remains unaccounted for," the MAIB said.
"As well as continuing to gather witness accounts, further investigation work will look to establish the navigational practices onboard both vessels, the manning and fatigue management, the condition and maintenance of the vessels involved, and the environmental conditions at the time."
A salvage plan for both ships is being developed.
Crowley said Stena Immaculate was carrying 220,000 barrels of jet fuel in 16 segregated cargo tanks, at least one of which was "ruptured" when it was struck.
The tanker was operating as part of the US government's tanker security programme, a group of commercial vessels that can be contracted to carry fuel for the military when needed.
It had been anchored while waiting for a berth to become available at the Port of Killingholme, on the River Humber, Crowley said.
Aerial surveillance flights on Wednesday did not identify any pollution on the surface of the water, the coastguard added.
