"MY HEART BLEEDS"

The Indonesian pilot was experienced and the plane last underwent maintenance in mid-November, the airline said. The aircraft had accumulated about 23,000 flight hours in some 13,600 flights, according to Airbus.

Malaysia AirAsia chief Tony Fernandes flew to Surabaya and, along with Indonesian officials, updated distraught relatives of passengers at a crisis centre at the airport in Indonesia's second-largest city.

"Keeping positive and staying strong," he said on Twitter.

"My heart bleeds for all the relatives of my crew and our passengers. Nothing is more important to us," he said.

Indonesia's Transport Ministry said the government would review AirAsia's Indonesian business unit to improve safety.

Indonesian President Joko Widodo urged people to pray for the safety of the passengers and crew. Such sentiments were echoed by other world leaders, including Pope Francis.

Louise Sidharta was at Singapore's Changi Airport waiting for her fiancée to return from a family holiday.

"It was supposed to be their last vacation before we got married," she said.

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