One sailor has died and four are missing after a British cargo ship sank following a collision with another vessel in the North Sea.
British-flagged Verity collided with Bahamas-flagged Polesie early on Tuesday morning about 14 miles south-west of the German archipelago of Helgoland, Germany's Central Command for Maritime Emergencies said.
Verity, which measures 91ft, reportedly sank with seven people on board. A signal from the ship was lost at about 5.20 a.m and wreckage was found.
Two sailors have been rescued in an ongoing search and rescue operation, according to German authorities. They were said to not be in life-threatening condition.
The body of one man was recovered, while four were still missing, the emergency command said.
"We are now doing everything humanly possible to rescue more people alive," the head of the emergency command, Robby Renner, said at a news conference in Cuxhaven.
The water temperature at the time of the collision was about 12 C (54 F), which experience shows that people can survive for about 20 hours, said Michael Ippich of the German Maritime Search and Rescue Service.
Several rescue ships and aircraft taking part in the search hadn't located the missing crew members by late afternoon. Rescuers considered the possibility that they were still inside the Verity and sent divers down to the wreck at a depth of about 30 meters (around 100 meters) to check whether there were any signs of life.
But the divers were unable to find anything, and increasingly strong currents meant that they couldn't immediately try again. Visibility at the site was low and any dives could only be made in a short window between tides.
P&O Cruises ship Iona also joined the search on Tuesday morning, after pausing en-route to the Netherlands to provide help.
The Iona has doctors on board and could treat people if needed, authorities said.
More medical personnel were being taken to the scene by helicopter.
The search and rescue operation was taking place amid 10ft waves and winds of 30mph, MailOnline reported.
Verity, which was built in 2001 and was carrying steel coils, was heading from Bremen in Germany, to the English port of Immingham in north-east Lincolnshire when the incident happened.
Polesie, which was reportedly travelling from Hamburg to La Coruña in Spain, remained afloat with 22 people on board. The ship is more than twice the length of Verity, at around 190m.
There was no immediate explanation of the cause of the collision.
A P&O Cruises spokesperson said on Tuesday morning: "“P&O Cruises Iona is currently involved in a search and rescue operation off the coast of Germany.
"The incident is ongoing and Iona’s cooperation complies with international maritime law as well as being consistent with the company’s moral and legal obligations. Iona is scheduled to be at sea today and this event should have no impact upon tomorrow’s scheduled call to Rotterdam or the onward itinerary.”
Heligoland is located 46km (29 miles) north of the German coastline.
Faversham Ships Ltd, which owns the Verity, described the incident as "ongoing" and said it is working with local authorities.
The Foreign Office has been approached for comment.