A stricken cargo ship has sunk in rough weather a day after its crew was rescued during an earlier storm.
The Greek-registered Ice Prince went down about 26 miles (42km) off Portland Bill, Dorset, after shedding more than 2,000 tonnes of its timber cargo.
Twelve crew were airlifted to Dorset and eight taken by lifeboat to Devon.
Coastguards said the risk of oil pollution was low, but they were concerned a "wood slick" of the cargo could be a hazard to shipping.
A coastguard spokesman said the ship sank at about 0045 GMT on Tuesday after being monitored through the night by two tugs.
Waves had reached 9ft (2.7m) and there were strong winds.
The Ice Prince, which weighs 6,395 tonnes and is 328ft (100m) in length, sent out its initial emergency call at about 1900 GMT on Sunday.
Rescuers battled gale force winds and rough seas with 16ft (5m) swells to evacuate the men from the vessel in a mission one lifeboatman described as a "once-in-a-career" rescue.
Twelve of the crew were airlifted to Portland, Dorset, and eight others taken by lifeboat to Brixham, Devon.
It is understood the members of the Ice Prince's crew were all foreign nationals and were wearing lifejackets and immersion suits when rescued.
The vessel was carrying 5,258 tonnes of sawn Swedish red and white timber. About 2,000 tonnes of the cargo was being carried on the deck and a quantity of wood - about 3,000 tonnes - is still believed to be in the hold.
It was also carrying an estimated 400 tonnes of fuel oil and other lubricating oils in its engine spaces.
The ship settled about 26 miles (42km) south-south east of Portland Bill, with its stern settling on the sea bed and leaving her bow about 5m (16ft) out of the water for several hours before it went completely underwater.
A counter-pollution aircraft was sent to the scene to survey the area and a salvage headquarters has been set up at Weymouth's Customs House.
Coastguards said they were expecting a "wood slick" to end up somewhere on the south coast over the next few days. Police forces have been alerted.
Helicopters have been checking the area for any signs of for oil pollution.
Kelly Reynolds of the Maritime and Coastguard Agency said initial surveillance showed that the risk of pollution was low.
She said; "We've seen a slight sheen coming from the vessel, but that is to be expected considering that the engine room is flooded.
"But the main tanks with the fuel oil are still intact, so the pollution risk at this present time is very low."
She said that coastguards were more concerned with the 10m (33ft) lengths of wood.
She said: "We believe it is a danger to navigation because there are bundles of wood that are breaking down into loose planks."
Warnings have been sent to all shipping in the area to avoid floating timber and emergency navigational buoys are due to be added in the area on Wednesday.
Underwater surveillance equipment is also due to be used on the sunken vessel on Thursday to assess the condition of the hold and the viability of removing any fuel oil.
A 1,000m (3,280ft) temporary exclusion zone is in place around the ship.