MADRID (AP) — Spanish and Portuguese airport authorities say that an American Airlines flight heading to Barcelona from New York was forced to make an emergency landing in northwest Portugal because of technical problems.

Airport authorities told The Associated Press on Sunday that the incident occurred when the pilot of Flight AAL66 requested clearance for an emergency landing. The plane then landed safely in Porto without further incident.

All 151 passengers, along with eight crew members and three officers aboard the Boeing 767-300 aircraft, were accommodated in hotels. The plane was inspected and wasn't cleared to continue on to Barcelona.

American Airlines later chartered a Sunday night flight through Portuguese airline TAP in order to transfer the passengers to Barcelona.

The technical problems that prompted the emergency landing weren't immediately clear.