The Norman Atlantic, carrying almost 500 passengers and crew and more than 200 vehicles, was 44 nautical miles northwest of the island of Corfu when it sent a distress signal after a fire started in the lower deck, Greek coast guard officials said.
It was unclear whether there had been casualties or if any passengers were in the water, though one man on board said strong winds were stopping rescuers from getting close.
“We are burning and sinking, no one can save us,” Nikos Papatheodosiou told Greek TV by telephone. “Please help us! Don’t leave us,” he said before hanging up.
Cold winter temperatures would make survival in the sea difficult unless rescue came quickly.
Passengers said they were waiting on the upper deck of the ship as shipping inister Miltiadis Varvitsiotis said the combination of very bad weather, with winds of up to 88 kilometres per hour and the fire, made the operation extremely complicated.
“We are doing everything we can to save those on board and no one, no one will be left helpless in this tough situation,” he said. “It is one of the most complicated rescue operations that we have ever done.”
He did not confirm earlier reports that as many as 130 people had been rescued, saying only that 35 people had been able to board a nearby container ship, the Spirit of Piraeus, from a rescue boat carrying 150.
Conditions made it difficult for the boat to re-approach the cargo ship.
Mr Varvitsiotis said there were 478 passengers and crew aboard the ship, more than the 466 originally reported. Of those, 268 were Greek. There were no immediate details of the nationality of other passengers.
While rescue vessels and aircraft had been dispatched to the scene, early rescue work was being coordinated from nearby passenger and cargo ships. A fire-fighting vessel was trying to approach the ferry.
The fire broke out in the lower deck garage of the vessel but there were differing reports of when it started.
Officials said both Italian and Albanian authorities were taking part in the operation, which was being conducted in extremely difficult conditions with strong winds, heavy seas and very cold temperatures.
Rescue helicopters and a C-130 search-and-rescue support aircraft had also been sent.
