Hopes are fading of finding any more survivors from the plane crash off the coast of Libya which claimed at least 17 lives.

Five passengers remain missing - three Libyans, a Briton and a Filipino.

Of the 41 oil workers and crew on board the Swiss-chartered plane, 19 are known to have survived.

Salvage workers are preparing to recover the wreckage of the plane that came down in the Mediterranean sea on Thursday.

The plane was flying from the Libyan capital Tripoli to the country's main petro-chemical facility at Marsa el-Brega, 600km to the east.

The BBC's correspondent in Geneva, Claire Doole, says strong winds and heavy rain are hampering the search for survivors.

In a statement issued before the rescue of a Briton on Friday, the Swiss Transport Ministry suggested that the passengers still missing had probably not survived.

"The Air Accident Investigations Office has learned that 23 people were most probably killed when the Shorts 360/300 plane crashed during an emergency landing on water," the statement said.

A Libyan official released details of the condition of the survivors.

Both engines failed

"All the survivors are in good health. Some of them have received care at the company's clinic in Marsa el-Brega. Procedures have started for the repatriation of the bodies of the dead," the official said.

"We stopped searches last night because the visibility was not good, and we resumed them early this morning on sea and on land," he added.

The twin-propeller aircraft is believed to have vanished from radar screens at 1230 GMT on Thursday, two hours after taking off from Tripoli.

Minutes before the crash the pilot radioed Libyan air traffic control saying that he was attempting an emergency landing on water after both engines failed.

The British-built Shorts 360 aircraft was leased to the Sirte Oil Co in Libya to transport workers between its headquarters and various oil fields. All the passengers were oil workers, and the plane had a crew of three.

There is speculation that fuel levels could have played a part in the crash in which both engines failed in the moments before the plane went down.

A survivor calls home

Air travel specialists say that double-engine failure is very rare because very few aircraft systems simultaneously affect both engines.

But lack of fuel, or fuel that has been contaminated, would be a possible cause of such a failure.

Stewart Bonar, an oil worker from Limavady in Northern Ireland, is being treated in hospital in Libya for broken bones.

In a conversation with his wife, Olive, Mr Bonar expressed deep sadness at the death of his colleagues.

Mrs Bonar said: "He said he had had a lot of X-rays taken and he is very, very upset, obviously and very annoyed about his two mates who he travelled with all the time and worked with. They are both dead."

"I asked him how did he get out of the plane, but he just said he really didn't want to talk about it, he just said 'I'm alive'," she added.

The investigation

Swiss officials said the Libyan civil aviation authority, aided by two British experts and one from Switzerland, would lead the investigation into the crash.

According to international air travel regulations the investigation could be led by Libya, Switzerland or Britain, the country where the plane was manufactured.

Britain's Department of Transport said its involvement would be on two levels - because there were British fatalities and because the plane was built in Northern Ireland.

The department also offered its facilities and expertise in reading the aircraft's flight data recorder when required.