Investigators in Cyprus say the investigation into Sunday's crash of a Helios Airways jetliner in which everybody on board died is focusing on the air supply system. The government has ruled out terrorism as the cause of the crash.

A spokesman for Helios Airways has confirmed its fleet has been grounded since the crash. Following reports of prior problems with maintenance of the airline's planes, crew and passengers at Larnaca airport refused to board an aircraft belonging to the company.

The airline operates a fleet of Boeing B737 aircraft and runs daily services to London, Athens and Prague. Established in 1999, Helios is the first independent, private-owned airline in Cyprus.

Following the crash, the airline came under withering criticism from the public for waiting more than six hours before releasing information about the fate of the passengers.

Albert Coutounzian lost several relatives in the crash.

"I lost my whole brothers family, two kids, my brother and his wife. It's really, I don't know, it's a tragedy," he said.

News programs on local Cypriot and Greek radio broadcast calls from several listeners who claimed that they had experienced problems with the air-conditioning on Helios flights. According to the Cyprus Mail newspaper, one caller claimed that on a flight back from Prague earlier this week; temperatures fell dramatically minutes after leaving Larnaca.

John Leonidou a reporter with the paper told VOA that passengers had bombarded TV stations with their own accounts of past flight problems.

"One passenger said that he had been on a previous flight of Helios, and said that 20 minutes before landing that temperatures suddenly dropped and he was very cold and stewardesses were handing out blankets to passengers. Several other people phoned in with similar experiences. Another person called in and said water was continuously dripping on him and when he asked the steward what the problem was the steward said to him they were having problems with the air conditioners," he said.

None of the claims was independently verified. While the cause of the tragedy is under investigation, some news agencies report investigators are concentrating on the loss of oxygen as the likely culprit. The government has ruled out terrorism as a likely cause.