All passengers have now been evacuated from a stricken passenger ferry in the Adriatic, the Italian Coast Guard said.
Seven people died after the Norman Atlantic caught fire yesterday morning as it sailed from the western Greek port of Patras to Ancona in Italy.
At least four Britons were rescued from the ship, which was carrying 422 passengers and 56 crew members.
Among them was British showjumper Nick Channing-Williams, who was reunited with his Greek fiancee Regina Theoffili after they were separately rescued from the blazing vessel.
A photograph sent to his family by a member of the Italian Air Force shows a grinning Mr Channing-Williams covered in black soot and oil after he spent more than a day trying to avoid acrid fumes.
Mr Channing-Williams described how he and other passengers had tried to tie tow ropes from tug boats on to the front of the ferry but gave up after it repeatedly snapped.
He told Sky News there were moments when he was "absolutely terrified" and did not think he would live through it.
Speaking after being reunited with Ms Theoffili, he said: "That was quite an emotional reunion because we were separated for a few hours which was not very nice and in the early hours of this morning I was starting to question whether we were going to get off it or not."
A cargo ship carrying 49 people evacuated from the ferry arrived in the Italian port of Bari this morning, though it is not known if the Britons were among them.
A spokeswoman for the Foreign Office said: "From the passenger manifest, and other information available to us, we know that a number of British nationals were on board the Norman Atlantic.
"Local authorities have confirmed to us that four British nationals have been rescued so far. The rescue operation is ongoing and we remain in close touch with the Italian authorities."
Some 300 people have been rescued but more than 160, including a number of Britons, remain on board the smoke-stricken ferry which is now adrift in rough seas between Italy and Albania.
One British passport holder has been evacuated, as have three other Britons who have dual citizenship but were travelling on different passports.
It was thought a second British passport holder - Nick Channing-Williams, a British showjumper based in Greece - had been airlifted to safety with his Greek fiancee, Regina Theoffili.
But his family have said Italian officials informed them that, while she has been rescued, he is still on the boat.
His mother, Dottie, from Berkshire, said the family were "very, very worried" and had been up all night trying to find out what had happened to him.
She told the BBC that a Greek minister phoned Ms Theoffili's family yesterday and told them the couple were both being airlifted off.
But she later learned that while her son's fiancee was now being treated in hospital, Mr Channing-Williams remains on the ship and is in a small group of passengers who have become separated from a larger group.
Mrs Channing-Williams said: "We have had a message to say that he hopes that Regina made it because it feels like 'no boats around and only the helicopter. We are six people who tried to get the boat towed, maybe you could call someone as six of us are stuck in the front and there are no boats close by'.
"We think has happened is that they are changing the rescue into helicopters more than boats, and the Foreign Office has said that there are in fact 200 people at least on board, so they are not on their own, these six people.
"But they have obviously got separated, and knowing Nicholas - 'Oh yes, well, I will help you out with that' - and they have obviously lost the other big group, so I am not quite sure what is going to happen with that, so that is all very worrying."
Mrs Channing-Williams said she had not heard from her son directly since yesterday.
She said: "The gentleman that telephoned us to say that Regina had arrived at the port and was being taken to hospital, said that he (Nicholas) was in good spirits, so we know that he is there, we know he is on board, but we also now know that he has become separated from the large group, so it is just a rollercoaster.
"One minute you think everything is fine and the next minute you are very, very worried indeed, so it is very hard."
Mrs Channing-Williams said her son regularly took the ferry from Greece to Italy, and would then drive to the UK.
She said: "That is what he was doing this time - he was coming over to look at horses and then spending New Year's Eve with us, and now we just hope that they are going to be both OK and we can put this behind us."
hree other Britons, dual citizens travelling on non-British passports, have also been rescued.
Susan Daltas said her daughter Mia and two granddaughters had been lifted to safety.
"I've heard recently from Marcus, our son-in-law, who kept the phone, that they've been airlifted to safety - the two little girls and Mia. But he's still on the ferry, as far as we understand," Mrs Daltas told the BBC.
"They sent the two girls quite a long time before Mia, which worried us a little because they're too young to be without their mother, especially after all that worry and fright. They must be terrified."
She said her youngest granddaughter had been taken to a mainland hospital.
"She was suffering from hypothermia because they didn't even manage to get a coat out of the cabin before they had to go on deck. But apparently she's now sleeping," she said.
Of her son-in-law, Mrs Daltas said: "He was shaken, obviously, but I think he'd been staying strong for the family, and the minute they were safe he went a bit wobbly. It's just cold, and he said his mobile was soaking wet because they had to keep moving around the boat to get away from the fire. So it's obviously not pleasant."
High winds and bad weather have hampered efforts to rescue the remaining passengers from the ferry. Italian and Greek ships have helped lift people from the ship, and some were led to safety aboard nearby merchant ships.
Helicopters also carried out rescue operations throughout the night, battling gusts of almost 50mph as they lifted passengers from the vessel. Others stuck on board were given blankets while they waited to be saved.
One man has died during the incident, while his wife was injured. The pair were found in a lifeboat rescue chute, the Italian Navy said.
The fire broke out before dawn yesterday on a car deck of the Italian-flagged Norman Atlantic. Passengers huddled on the vessel's upper decks throughout the day and night, pelted by rain and hail.