At least 12 are thought to have died and hundreds of passengers rescued from a burning Greek ferry sailing from Greece to Italy.
Rescue workers say nearly 40 passengers remain unaccounted for, but it is unclear whether that is due to inaccurate manifest lists.
Two Albanian seamen who took part in the rescue operation on a tugboat are thought to be among the dead.
Rescue helicopters worked through the night to lift more than 420 passengers to safety while Italian and Greek Navy ships joined in to aid the evacuation of the burning vessel .
A total of 478 passengers and crew members were on board the boat, operated by Greek ferry company ANEK Lines, which caught fire west of the Greek holiday island of Corfu, while sailing the Adriatic Sea from the Greek port of Patras to Ancona in Italy.
The Italian-flagged ferry boat 'Norman Atlantic' was operating as a temporary replacement for the normal ANEK Lines ferry which is currently undergoing annual maintenance.
Rescue operations have been hampered by poor weather, rough seas and high winds. Rescue helicopters have worked through the night lifting passengers off the burning ferry and transferring them to nearby vessels.
Greek and Italian helicopters made repeated trips to the boat to airlift passengers from countries that include Britain, Greece, Germany, Italy, Austria, Turkey, France and the Netherlands to safety.
At least seven merchant ships, in the area at the time of the fire breaking out on Sunday morning, have joined the rescue effort and have surrounded the stricken vessel to form a barrier against the high winds.
Greek Maritime Minister, Miltiadis Varvitsiotis, said the very bad weather, with winds of up to 55 miles per hour, has hindered the rescue operations.
He said: "We are doing everything we can to save those on board and no one will be left helpless in this tough situation. It is one of the most complicated rescue operations that we have ever done."
Attempts to tow the boat to safety have failed but the fire is now thought to be under control. Greek and Italian Navy ships have arrived to help in the coordinated rescue effort while fire tugs are spraying the burning ferry with seawater to help extinguish the blaze.
Eye witnesses report that passengers were unable to reach lifeboats because the decks where they were stored were too hot to walk on and shoes melted on the deck surface.
Passengers huddled on decks, away from the fire and fumes, but suffered cold winds and freezing temperatures as they waited to be rescued
The first rescue ship carrying 49 people evacuated from the ferry arrived at the Italian port of Bari early today while 100 people were taken off the ferry during the night, according to reports from the Italian coastguard.
Meanwhile an investigation has already begun into how the vessel caught fire. The Norman Atlantic has a capacity of carrying around 220 vehicles and many of those on board are thought to be lorry drivers.
According to initial reports the blaze broke out in the exterior garage of the vessel at around 6am on Sunday. Italian news reports say the fire broke out on the ferry's vehicle deck before spreading.
Some passengers managed to board life rafts but the rough seas prevented many more from evacuating the ship.
The chief executive of the Italian Visentini group that owns the vessel said the ferry had passed a recent technical inspection and the boat was in "full working order", according to reports from the Italian news agency Ansa.