A United Airlines flight landed safely Tuesday in Honolulu after an engine cover came off during its flight from California, the airline said.
"Our pilots followed all necessary protocols to safely land the aircraft," United said in a statement, adding that all passengers departed the Boeing 777 normally at the gate.
The airliner landed as emergency responders waited nearby, said Hawaii Department of Transportation spokesman Tim Sakahara.
Flight 1175 was traveling to Honolulu from San Francisco.
Images posted on social media show an engine with the exterior cover missing as the plane approaches Honolulu.
Emergency crews can be seen waiting as the plane lands. One photo shows workers at the airport inspecting the damaged engine.
An emergency was declared due to a vibration in the right engine, said Federal Aviation Administration spokesman Ian Gregor said in an email.
The FAA will investigate.
Associated Press writer Paul Elias in San Francisco contributed to this report.Copyright 2018 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.