SINGAPORE, Dec. 28  -- People were seen to be brought into the waiting area of Singapore's Changi Airport hours after an AirAsia flight lost contact with air traffic authorities on Sunday morning.

The Civil Aviation Authority of Singapore said that Indonesian authorities have activated search and rescue operations and that the Singapore Rescue Coordination Center has also been activated and has offered help to Indonesian authorities.

"Two C130s are already on stand-by for this purpose. We remain ready to provide any assistance to support the search and rescue effort," it said.

The Civil Aviation Authority of Singapore and Changi Airport Group have also activated a crisis management center.

"A waiting area, and all necessary facilities and support have been set up for relatives and friends of the affected passengers at Changi Airport," it added.

The flight QZ8501 took off from Surabaya, Indonesia at 5:20 a.m. local time (6:20 a.m. Singapore time, or 2220 GMT) and was scheduled to arrive at Singapore's Changi Airport at 8:30 a.m. ( 0030 GMT).

Singapore air traffic control was informed at 7:54 a.m. that the flight lost contact with Jakarta air traffic control at 7:24 a. m. local time on Sunday.