Greek officials investigating the crash of a Cypriot airliner near Athens last year say a series of human errors in the cabin and on the ground led to the disaster.

A report issued Tuesday says the Helios Airways (Boeing 737-200) jet lost oxygen after taking off from Larnaca because its pressurization switch was left in a manual position before the flight.

The pilots and passengers fell unconscious, and the plane flew for nearly two hours on autopilot before running out of fuel and crashing into a hillside east of Athens in August 14, 2005.

All 121 people on board the jet were killed. The flight was bound for Prague via Athens.

Greek investigators faulted the pilots for not changing the pressurization switch to automatic, which would have allowed the cabin to pressurize by itself. The pilots then failed to react to an automatic warning of the problem in the cockpit.

The report also blames Helios Airways for deficiencies in its organization, and criticizes Cypriot regulatory authorities for inadequately executing their safety responsibilities.

The plane's maker, Boeing, is faulted for ineffectively responding to previous pressurization incidents with the same aircraft.

The Greek air force scrambled several F-16 jets to shadow the plane after radio contact was lost. The air force pilots reported seeing a flight attendant, who was still conscious, wrestling with the controls inside the cockpit, minutes before the crash.

Some information for this report was provided by AFP, AP and Reuters.