AirAsia QZ8501: Indonesia plane search resumes

"Based on our coordinate estimation, initial estimation is [the plane is] in the water," said Bambang Soelistyo, head of Indonesia's search and rescue agency, speaking in Jakarta.

However, no evidence has so far been found of the plane's whereabouts.

Officials in Surabaya, from where the plane took off, said search teams were only just reaching the area.

The Airbus A320-200 disappeared over the Java Sea early on Sunday on a flight to Singapore.

The pilots had requested a course change due to bad weather but did not send any distress call before the plane disappeared from radar screens.

"Based on the coordinates given to us and evaluation that the estimated crash position is in the sea, the hypothesis is the plane is at the bottom of the sea," Mr Soelistyo told a press conference.

"That's the preliminary suspicion and it can develop based on the evaluation of the result of our search," he said.

That search was largely suspended as night fell on Sunday.

Although some ships continued the hunt overnight, the main search planes and vessels, from several nations, only resumed at first light on Monday.

Mr Soelistyo said Indonesia was providing 12 ships, three helicopters and five military aircraft.

Indonesian transport ministry official Tatang Kurniadi said: "Our primary task is to find the plane. We are co-operating with every possible department, and relevant countries.

"This includes the department responsible for aircraft design, the aircraft manufacturer from France, and relevant operational teams from AirAsia and Malaysia."