Hong Kong - A packed passenger plane flying to Los Angeles was forced to return to Hong Kong when flames shot out of one of its engines around an hour into the flight, a news report said Saturday.

The Cathay Pacific Boeing 747-400 with 369 passengers shut down the engine and dumped fuel at sea before returning to Hong Kong early Thursday as problems developed while it flew over Taiwan.

Passengers reported seeing flames shooting out of an engine before the aircraft spent over an hour dumping fuel to allow it to land safely back in Hong Kong, the South China Morning Post reported.

Hong Kong's Civil Aviation Department is investigating the incident, which a Cathay Pacific spokeswoman told the newspaper was connected to an oil pressure problem in the engine.

The incident came just four days after a flight by Cathay Pacific's subsidiary Dragonair returned to Beijing after smoke entered the passenger cabin and oxygen masks dropped down. (dpa)