Boeing says it is monitoring reports on Malaysian Airlines flight MH370 which has gone missing.
The Boeing 777-200 aircraft which was bound for Beijing, China from Kuala Lumpur lost contact with air traffic control more than two hours into the flight.
Boeing said in a tweet: "We're closely monitoring reports on Malaysia flight MH370. Our thoughts are with everyone on board."
The B-777 has had a solid safety record since its introduction two decades ago.
The latest incident involving the aircraft was in July last year when a B-777-200 operated by South Korea's Asiana Airlines skidded off the runway upon landing at San Francisco's international airport.
Three people died in the accident.
Saturday's MAS flight was carrying 227 passengers and 12 crew members.
There were no Singaporeans on board. More than six in 10 were China nationals.