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.

Cathay Pacific Airways Ltd. canceled dozens of flights Tuesday after detecting an engine fault in one of its Airbus SE A350 aircraft. The mid-flight discovery of the problem forced the Zurich-bound flight to return to the carrier’s base in Hong Kong.

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.