An AirAsia flight carrying 162 people from Indonesia to Singapore has lost contact with air traffic controllers.
Indonesian Transport Ministry official Hadi Mustofa said Flight QZ8501 stopped communicating with the Jakarta air traffic control tower at 7.24am local time.
He said the plane had asked for an unusual route before contact was lost with Indonesia’s Juanda International Airport in Surabaya.
The flight was expected to arrive in Singapore at 8.30am local time (12.30am UK time).
An AirAsia statement said there were 155 passengers on board; 138 adults, 16 children and one infant.
Also on board were two pilots and five crew members.
Most of those on board – 156 – were from Indonesia, with three from South Korea, and one each from France, Malaysia and Singapore.
Authorities had initially said that one Briton was aboard the plane.
According to air traffic control website Flight Radar , the aircraft was travelling at 32,000-feet over the Java Sea when contact was lost.
Aviation expert Doug Maclean told Sky News that all the evidence suggests that “something very serious” has happened.
A statement on Malaysia based AirAsia’s Facebook page said: “AirAsia Indonesia regrets to confirm that Flight QZ8501 from Surabaya to Singapore has lost contact with air traffic control at 07.24hrs this morning.
“At the present time we unfortunately have no further information regarding the status of the passengers and crew members on board, but we will keep all parties informed as more information becomes available.
“The aircraft was an Airbus A320-200 with the registration number PK-AXC. At this time, search and rescue operations are in progress and AirAsia is cooperating fully and assisting the rescue service.”
The airline has set up an emergency call centre for family or friends of those who may have been on board the aircraft.
A statement issued by the Singapore Civil Aviation Authority said: “The Singapore Rescue Coordination Centre has offered help to the Indonesian authorities. Two C-130s are already on stand-by for this purpose.
“Crisis Management Centres have already been activated. We are working with the airline’s crisis management team. A waiting area, and all necessary facilities and support have been set up for relatives and friends of the affected passengers at Changi Airport Terminal 2.”
The incident comes at the end of a difficult year for Malaysia’s airlines. National flag carrier Malaysia Airlines lost two aircraft this year.
Flight MH370 went missing on 8 March on a trip from Kuala Lumpur to Beijing with 239 passengers and crew on board.
On 17 July, Flight MH17 was shot down over Ukraine, killing all 298 people on board.
:: Relatives or friends of those aboard the plane can contact the AirAsia hotline on: +62 212 985 0801.