Hong Kong aviation investigators say an engine problem that caused Cathay Pacific to ground its entire fleet of Airbus A350 jets for inspection earlier this month could have escalated into “extensive damage.

Hong Kong's air safety authority said Thursday that a defect in an engine component of a Cathay Pacific Airways Airbus A350 that caused a fire, forcing a Zurich-bound flight to return to Hong Kong, could have caused ''extensive damage'' to the aircraft.

An engine defect in the Airbus A350 plane that led to the cancellation of dozens of Cathay Pacific flights in early September could have escalated into "extensive damage", according to the results of a Hong Kong probe released Thursday.