Most of the bodies recovered from a Cypriot plane that crashed near Athens with 121 people on board were frozen solid, a Greek official said, suggesting the airliner was a flying tomb before it plunged to earth.
As accident investigators combed the crash site for clues, aviation experts were baffled at what appeared to have been a catastrophic failure of cabin pressure or oxygen supply in freezing temperatures at 35,000 feet - nearly 10 kilometres up, higher than Mount Everest.
One expert said reports of extreme cold suggested there was no air circulating in the cabin.
"Autopsy on passengers so far shows the bodies were frozen solid, including some whose skin was charred by flames from the crash," the Defence Ministry source, with access to the investigation, told Reuters yesterday.
The Helios Airways Boeing 737 was carrying 115 passengers and six crew when it crashed 40 kilometres north of Athens on Sunday. There were no survivors.
Rescue workers recovered the body of the pilot, a German identified as Martin Hans Gurgen, and said they had found the plane's black box flight recorders, including the one that records pilot conversations, and would send them to France for analysis.
The recovery of the black boxes is crucial to determining the cause of the worst air disaster in Greece and the worst involving a Cypriot airline.
Greek TV reported on Sunday that the pilot had told air traffic controllers the plane was experiencing problems with its air conditioning system shortly before contact was lost.
A passenger list released by Cyprus' Transport Ministry showed a family of four Armenians living in Cyprus, 12 Greeks and 104 Cypriots were killed in the crash. There were 17 children under the age of 16 on board, the youngest aged four.
Relatives of some victims were on their way from Cyprus to the crash site to start the grim task of trying to identify loved ones. At Larnaca airport in Cyprus, from where the doomed plane took off, crew and passengers yesterday refused to board an aircraft belonging to Helios Airways, the state-run Cyprus News Agency reported.
About 100 passengers due to fly from Larnaca to Sofia demanded to travel on planes of other airlines. "First the crew refused to board, then the passengers," the agency said.
But a Helios spokeswoman denied a Cyprus Transport Ministry statement that its planes had been grounded.
The Mediterranean island of Cyprus started three days of mourning with flags at half mast in a long weekend holiday that is the busiest of the summer for Greeks and Cypriots.
The plane was on a flight from Larnaca to Prague with a stop in Athens. Greek authorities ruled out any hijacking or terrorism links to the crash.
The flight was declared "renegade" when it entered Greek air space and failed to make radio contact. Two F-16 air force jets were scrambled to investigate and reported that the co-pilot was slumped in the cockpit and the pilot was not visible.
Defence Ministry officials said 90 minutes elapsed between the alert being raised and the plane crashing at 12.03 p.m.
Greek government spokesman Theodore Roussopoulos said the F-16 pilots reported that with the pilots out of action there may have been a last-gasp effort by others on the plane to bring it back under control.
"The F-16s saw two individuals in the cockpit seemingly trying to regain control of the airplane," Mr Roussoupoulos said. It was not known if they were passengers or other crew.
"The F-16s also saw oxygen masks down when they got close to the aircraft. The aircraft was making continuous right-hand turns to show it had lost radio contact."
A passenger on the doomed plane said in an SMS text to his cousin in Athens: "The pilot has turned blue. Cousin farewell, we're freezing."