Initial autopsies showed that at least six of the 121 people aboard a Cypriot plane were alive but not necessarily conscious when the aircraft crashed while on autopilot, a coroner said Monday, as authorities struggled to explain the actions of the pilot and crew.

The results of the first six autopsies shed some light on the final minutes of Helios Airlines (search) Flight ZU522, which crashed Sunday into a hillside in suburban Athens, killing all 115 passengers and six crew members. But they failed to answer all the questions.

In Larnaca (search), the Cypriot city where the flight took off, police raided the offices of Helios Airlines, seeking "evidence which could be useful for the investigation into possible criminal acts," said Cypriot deputy presidential spokesman Marios Karoyian.

Greek aviation officials have said the plane apparently lost pressure suddenly, causing a rapid loss of oxygen on board. In that case, passengers and flight crew would have had only seconds to put on oxygen masks before losing consciousness amid subzero temperatures. Death would be minutes behind.

But two fighter jet pilots who scrambled to intercept the plane saw the co-pilot slumped over, oxygen masks in the plane dangling, and two unidentified people trying to take control of the plane. The pilot was not in his seat when the plane crashed, about 2 1/2 hours after the crew first radioed in air-conditioning problems, officials said.

The fire department has said none of the bodies had masks on their faces.

"It's odd," said Terry McVenes, executive air safety chairman for the Air Line Pilots Association, International. "It's a very rare event to even have a pressurization problem and in general crews are very well trained to deal with it."

Athens' chief coroner, Fillipos Koutsaftis, said he could not determine whether the six people whose bodies were examined were conscious when the Helios Airways Boeing 737-300 (search) plunged 34,000 feet into a mountainous area near the village of Grammatiko, 25 miles north of Athens.

"Our conclusion is they had circulation and were breathing at the time of death," Koutsaftis said, but stressed: "I cannot rule out that they were unconscious."

Officials in the coroner's office said ongoing autopsies on another six bodies were likely to show similar results. They asked not be named because the results had not yet been publicly released.

Greek and Cypriot officials have ruled out terrorism as a cause of the crash.

Investigators, to be joined by U.S. experts, were sending the plane's data and cockpit voice recorders to France for expert examinations.

But the head of the Greek airline safety committee, Akrivos Tsolakis, said the voice recorder was damaged. "It's in a bad state and, possibly, it won't give us the information we need," he said.

The pilots of two Greek air force F-16 fighter planes scrambled to intercept the plane after it lost contact with air traffic control shortly after entering Greek airspace said they saw the co-pilot slumped over the controls. The pilot did not appear to be in the cockpit, and oxygen masks were seen dangling in the cabin.

The fighter jet pilots also saw two people possibly trying to take control of the plane; it was unclear if they were crew members or passengers.

The plane might have run out of fuel after flying on autopilot, air force officials said, asking not to be named in line with Greek practice.

Searchers still were looking for three bodies, including the plane's German pilot, fire officials said. The body of the Cypriot co-pilot was found in the cockpit.

After the crash, authorities said it appeared to have been caused by a technical failure — resulting in high-altitude decompression. A Cypriot transport official had said Sunday the passengers and crew may have been dead before the plane crashed.

U.S. aviation experts said they could not understand the behavior of the flight crew.

Jim Hall, former chairman of the National Transportation Safety Board, said it was possible that the oxygen in the cockpit failed.

He said the NTSB has been concerned about the ability of the pilots to get their masks on quickly enough.

"The accident did not have to occur," said Hall. "It has to be either a training issue or an equipment issue."

In a related development, police in northern Greece arrested a man who claimed to have received a telephone text message from a passenger. The man — identified as Nektarios-Sotirios Voutas, 32 — told Greek television stations that his cousin on board the plane sent him a cell-phone text message minutes before the crash saying: "Farewell, cousin, here we're frozen."

But authorities determined he was lying, and arrested him on charges of dissemination of false information.

A passenger list showed there were 20 children under the age of 16 on board, although the airline initially reported as many as 48 children were passengers.

Cypriot authorities identified the pilot as Marten Hans Jurgen, 50, from Berlin. Helios' general manager, Andrewas Drakos, said he did not know how long the pilot had worked for the airline.

A spokesman for the German Foreign Ministry, speaking on condition of anonymity in line with German practice, identified one of the pilots as a 58-year-old German but would not give his full name. It was unclear why there was a discrepancy in his age. Greek and Cypriot authorities often list surnames before given names, and Hans-Juergen would likely be the pilot's first name.

In Berlin, police were guarding the pilot's home in a quiet Berlin neighborhood near the Schoenefeld airport.

The name on the mailbox said Merten. Neighbors confirmed his first name was Hans-Juergen and said he was a pilot in his 50s, but refused to provide any other details.

The airliner's pilots had reported air conditioning system problems to Cyprus air traffic control about a half-hour after takeoff, and Greek state TV quoted Cyprus' transport minister as saying the plane had decompression problems in the past.

But a Helios representative said the plane had "no problems and was serviced just last week."

Helios said the Boeing 737-300 was manufactured in 1998 and previously operated by Deutsche BA. It entered the Helios fleet in April 2004, the company said.