The man arrested by Humberside police is the captain of the Solong cargo ship, the vessel's owner tells the BBC
Earlier, the police force said that a 59-year-old man has been arrested on suspicion of gross negligence manslaughter, following the North Sea collision
Assistant Chief Coastguard John Craig says flames are still visible on the Solong, with salvage plans in place for both vessels
One crew member of the Portuguese cargo ship is "assumed deceased", a UK minister says, as the transport secretary says both Solong and US oil tanker Stena Immaculate are expected to stay afloat
Owners of the cargo ship say it was not carrying sodium cyanide, as previously reported, but had four empty containers that had once held the toxic chemical
As we've reported, both ships are still on fire after colliding yesterday.
The Solong, a Portuguese-flagged container vessel, is thought to have collided with the Stena Immaculate, a US-flagged oil and chemical tanker.
Stuart Harratt
Live reporter
Image source, Getty ImagesIt's almost 24 hours since two ships collided in the North Sea, and both are still on fire.
A cargo ship carrying highly toxic chemicals struck an oil tanker carrying jet fuel just before 10:00 on Monday.
One crew member of the cargo ship is still unaccounted for and the search has been called off after "an extensive search", HM Coastguard says.
The collision involved the US-registered Stena Immaculate - which was transporting fuel on behalf of the US military - and the Portuguese-flagged Solong.
Coastguard Divisional Commander Matthew Atkinson said 36 people had been rescued, with one person taken to hospital.
Stick with us for the latest lines.
Imogen James
Live reporter
Image source, ReutersJust before 10:00 GMT, two vessels collided off the East Yorkshire coast in a busy shipping area.
Both caught fire. Twelve hours on, they are continuing to burn.
The Stena Immaculate - a US oil tanker - was hit by the Portuguese cargo ship, the Solong, while at anchor.
It came out of the blue, a tanker crew member told the BBC's Rowan Bridge. He and his colleagues were buying new clothes in the local Asda - they had no time to collect their belongings before being rushed onto lifeboats.
The coastguard said 36 people were brought ashore, one of whom was hospitalised.
Solong's owner, Ernst Russ, later shared that one member of its 14-strong crew was missing. This was confirmed by the coastguard as it announced that the search had been called off.
The Stena Immaculate was carrying jet fuel for the US government when it was struck, some of which is spilling into the sea, sparking concerns for the marine life in the area.
The Solong was carrying 15 containers of sodium cyanide among its cargo, according to a report. It's unclear if any has entered the water.
While we're starting to get a clearer sense of the events that led to the collision, many questions as to how and why it happened remain unanswered.
Our live coverage is ending now, but we'll continue to update you on all the latest developments in our main news story.
Jonathan Josephs
BBC business reporter
Image source, ReutersMy colleague Rowan Bridge said earlier that one of the crew from the Stena Immaculate that spoke to him in Grimsby was American. That’s consistent with what this ship was being used for.
In fact, the US military says it had been on a short-term charter to the US Navy's Military Sealift Command.
It is one of 10 vessels in the US government’s Tanker Security Program, which is designed to make sure the military can move things around if they need to, particularly in times of armed conflict or national emergency.
It’s a programme that harks back to World War One, when the US government found itself short of ocean-going capability. This led to the 1920 legislation known as the Jones Act.
It requires cargo vessels sailing between two US ports to be American flagged and registered, and to use at least 75% American crew. The expense of this means not many cargo vessels are US registered.
The US government plays a key role in supporting the viability of the vessels that do meet these requirements, such as by contracting them, so that in a time of national emergency the US has a homegrown merchant fleet to call on.
Image source, Getty ImagesCaptain Nigel Bassett tells BBC News that the investigation into this morning's collision will be looking at whether it was caused by machinery or personnel.
"Today, something has failed," he says.
Bassett explains that ships are designed to resist impact. The vessels of today are "double skinned", he explains, meaning there are two layers between the hull and the cargo.
"It is designed to withstand the rupture of the cargo space" but today both the internal and external hull appear to have been perforated, he adds.
The inquires into the incident should leave "no doubt" as to what happened, Bassett says.
Transport Secretary Heidi Alexander says she's "hugely grateful" to the coastguard, RNLI and emergency services that responded to the collision of two vessels in the North Sea this morning.
"They were on the scene swiftly, have helped rescue those in immediate danger and I know they will continue to work tirelessly over the coming days," she says in a written statement.
"My thoughts are with all those involved, especially the family of the missing crew member."
A preliminary investigation carried out by the Maritime Accident Investigation Branch (MAIB) has begun, she adds.
She says she will work closely with MAIB "as they conduct an assessment of any counter pollution response which may be required over the coming days".
We've got more detail now from the coastguard, which says both ships involved in the collision this morning remain on fire.
The divisional commander, Matthew Atkinson, says coastguard aircraft are "monitoring the situation".
We've just had an update from the coastguard, confirming that one crew member from the Solong cargo vessel remains missing.
Earlier, the BBC was told by the ship's owner Ernst Russ that one of the 14 crew was missing.
Matthew Atkinson, divisional commander for HM Coastguard says: "After an extensive search for the missing crew member sadly they have not been found and the search has ended."
He says 36 crew members from both ships were taken safely to shore, and one person was taken to hospital.
The Maritime and Coastguard Agency is assessing any necessary response to potential pollution, he adds.
He says "the incident remains ongoing and updates will be provided throughout".
Rowan Bridge
Reporting from Grimsby
Image source, Getty ImagesRNLI lifeboats were sent from multiple stations along the coast to assist at the scene
Some of the crew members from the Stena Immaculate oil tanker were at the local Asda in Grimsby this evening buying clothes.
None of them would speak on camera but I snatched a few words with one person.
They had boarded lifeboats and were towed into Grimsby and from what I could see they have escaped with very little.
He says he left the ship with just his wallet and his phone. The other crew members seemed to be in a similar situation.
He adds that the cargo vessel - Solong - just came out of the blue and crashed into them at a speed of 16 knots - as we reported earlier.
Greenpeace says it's "extremely concerned" about "multiple toxic hazards" from the North Sea ship collision.
We've been reporting that the cargo ship was carrying 15 containers of the toxic chemical sodium cyanide. It is not clear if this has entered the water.
The tanker was transporting jet fuel for the US government, some of which is spilling into the sea.
"As more information emerges about what the ships were carrying, we are extremely concerned about the multiple toxic hazards these chemicals could pose to marine life," Paul Johnston, a senior scientist at the Greenpeace Research Laboratories at Exeter University, tells the AFP news agency.
"The jet fuel that entered the water close to a breeding ground for harbour porpoises is toxic to fish and other sea creatures," he adds.
We're now starting to build up a picture of the events that led to the collision of two vessels in the North Sea today.
Here's BBC Verify's Nick Eardley with everything we know:
What we know about the oil tanker and cargo vessel collision
Rich Preston
BBC News
When a serious incident such as this happens at sea, vessels involved will send out a mayday signal. This is the highest level of urgency. It comes from the French m'aider - help me.
Captains of vessels will transmit information about their location, the nature of the emergency (in this case, "fire"), and how many souls are on board.
An order to abandon ship is typically the last resort for a captain experiencing an emergency.
Sailors will have been ordered to put on their lifejackets and go to lifeboats. Depending on the emergency, some people may not have had time to make it to a lifeboat or for lifeboats to be launched.
Life jackets and lifeboats will often be equipped with Emergency Position Indicating Radio Beacon (EPIRB). They usually activate automatically upon contact with water, and emit a distress signal which usually includes a GPS location.
On hearing a mayday signal, other vessels in the area will start making their way to the location to provide assistance.
The Laws of the Sea provide a duty to rescue. This is covered under the International Convention for the Safety of Life at Sea.
Unless it will put your own vessel or crew's safety at risk, nearby ships are required to provide assistance to any person in distress at sea, regardless of their nationality or status. Any ship attending and finding someone in the water will attempt to rescue them from the water and provide any emergency care they need.
Some vessels - including regular commercial vessels - have additional firefighting capabilities and therefore can be of greater assistance in cases like this.
More now from Ernst Russ, the owner of the Solong cargo ship. The company says both ships were damaged in this morning's collision.
"Both vessels have sustained significant damage in the impact of the collision and the subsequent fire," the company said in a statement.
One of the 14 crew members on the Solong cargo ship is missing, the vessel's owner Ernst Russ says.
The cargo ship's Hamburg-based owner says that "13 of the 14 Solong crew members have been brought safely to shore. Efforts to locate the missing crew member are ongoing".
The coastguard has not confirmed to the BBC whether it is still carrying out search and rescue operations.
Earlier we reported that all crew members were accounted for.
Earlier, we brought you some comments from Alastair Hay, a professor of environmental toxicology at Leeds University. We can bring you a bit more from him now.
He said it's still unclear how much of an impact sodium cyanide could have, because at this point we don't know if the chemical has entered the water.
“If the 15 containers are full, like you get on the back of truck, that is a lot of sodium cyanide. It would depend on how much was ruptured and what the leakage rate would be and what the currents were for dispersal in terms of the impact," Hay told the BBC.
The local coastguard should be taking samples "to understand the size of dispersal and where the risks would arise", he added.
“Sodium cyanide is highly soluble in water, and in contact with water there is a risk of some hydrogen cyanide gas being produced which could present a risk to any of those involved in rescue.”
We're seeing some images coming through showing members of the Bridlington Royal National Lifeboat Institution (RNLI) returning to their lifeboat station after being involved in the rescue operation earlier today.
According to the RNLI, teams from Bridlington, Mablethorpe and Skegness supported efforts to rescue people who were on board the two vessels that collided in the North Sea.
Image source, Getty Images
Image source, Getty ImagesWe've just had an update from P&O Ferries. It says the Humber Estuary - which enters inland towards Grimsby and Hull - remains closed to all traffic.
P&O says departure times from Hull and Rotterdam remain unconfirmed this evening, but adds it intends to resume the service once restrictions on the route are lifted.
Esme Stallard
Climate and science reporter
We understand that sodium cyanide was onboard the cargo ship that crashed into the oil tanker. We are not clear on whether any has leaked into the sea at this time.
Sodium cyanide is highly soluble in water and can be toxic as it affects the uptake of oxygen.
Alastair Hay, professor of environmental toxicology at Leeds University, tells the BBC that if it has come into contact with water “there is a risk of some hydrogen cyanide gas being produced which could present a risk”.
But he adds the impacts are all dependent on the scale of the dispersal, and as part of the clean up efforts, testing of the water will take place to determine the extent of any potential contamination.
Esme Stallard
Climate and science reporter
Now that the fuel type that the tanker was carrying has been confirmed it will help to inform the clean up operation.
Jet fuel has a high boiling point, so it will evaporate slowly. It is also relatively toxic, so marine life that comes into contact with it may be killed.
Jet fuel can be broken down in the water by bacteria and it appears from images some of it has already caught fire, so has been burnt off.
Dr Alex Lukyanov, researcher on advanced mathematical models of oil spills from the University of Reading, says predicting the exact impact at this time is a challenge as oil spills in the North Sea are affected by “multiple factors”, including sea currents, water waves and wind patterns.
But Alastair Grant, emeritus professor of ecology at the University of East Anglia, warns the environmental impacts could be severe: “Jet fuel is approximately 50 times more toxic to aquatic life than diesel oil, which in turn is more toxic than crude oil."
Jocelyn Timperley
BBC Future Planet
When oil hits the water, it's important to act quickly.
The sheer quantity of oil released can make them especially damaging. In 2024, around 10,000 tonnes of oil was released from tankers into the ocean, according to the International Tanker Owners Pollution Federation, external.
Doug Helton, regional supervisor of the emergency response division at the Office of Response and Restoration, external at the US's National Oceanic and Atmospheric Administration, recently spoke to the BBC for a long-read article on the limited progress we've made in cleaning up major oil spills.
The first step was to control the source, he said – "whether that be a ship, pipeline, or leaking well". Once the flow of oil is stopped, "the second priority is recovering oil at sea".
Oil spills spread rapidly, becoming a thin film a millimetre thick or less and covering a very wide area.
"Floating oil spreads very quickly and there is a limited window of time – days – when at-sea tools are effective," said Helton.
So what are the best ways to stop an oil spill from spreading, and can the oil ever be effectively cleaned up? Read on.