KUALA LUMPUR (REUTERS/AFP) - The Malaysia Airlines plane that went missing near the South China Sea early Saturday morning is presumed to have crashed, even as countries in the region joined in the search operation.
There were no reports of bad weather and no sign why the Boeing 777-200ER, powered by Rolls-Royce Trent engines, would have vanished from radar screens about an hour after it took off from Kuala Lumpur for Beijing.
A large number of planes and ships from several countries were scouring the area where the aircraft last made contact, about halfway between Malaysia and the southern tip of Vietnam.
Malaysian Prime Minister Najib Razak said 15 air force aircraft, six navy ships and three coast guard vessels had been pressed into service by Malaysia.
Vietnam dispatched two navy boats from Phu Quoc island and sent two jets and one helicopter from Ho Chi Minh City to search for the missing airliner. It was readying a further seven planes and nine boats to join the search effort.
China and the Philippines have also sent ships to the region to help. The United States, the Philippines, and Singapore dispatched military planes to help. The Republic of Singapore Air Force sent a C130 Hercules aircraft.
China has also put other ships and aircraft on stand-by, said its transport minister.
On Saturday night, Vietnamese authorities said it had spotted two large oil slicks about 15km to 20km long in the sea and was sending boats to the area.
Earlier in the day, Malaysian Prime Minister Najib Razak said that no sign has been found of flight MH370, which left KL at 12.41am with 227 passengers and 12 crew
The passengers were from 14 countries. Among them were 153 from China including 24 painters who had visited Malaysia to attend an art exhibition.
There were also 38 passengers from Malaysia and the others were from countries including Indonesia, Australia, France, New Zealand, Ukraine, Canada, India, Taiwan and the United States.
There were no Singaporean passengers although one of the passengers, Mr Tony Tan Wei Chew, 19, a Malaysian, had studied at St Andrew's Junior College here.
Datuk Seri Najib said he had spoken to Chinese Premier Li Keqiang and expressed condolences over the affected Chinese passengers. Mr Li had urged Malaysia to act quickly and vigorously in their rescue efforts.
Chinese President Xi Jinping called for emergency measures to find the plane, which had been due to arrive in Beijing at 6.30am.
He ordered the Ministry of Foreign Affairs and Chinese embassies and consulates to strengthen contact with relevant countries and pay close attention to the search and rescue work.
Singapore Prime Minister Lee Hsien Loong tweeted earlier that he had spoken to Datuk Seri Najib to express his sympathies over the missing plane and offer help with the search operations.
The airlines said the last radar contact was 2.40am local time, about 120 nautical miles east of Kota Bahru, near the South China Sea, MAS chief executive officer Ahmad Jauhari Yahya said.
Flight MH370 lost contact one minute before entering Vietnam's airspace.
He said there had been no indication the plane was in distress and that an early review showed that there was no bad weather.
In Beijing, tempers frayed as angry family members left a hotel near Beijng airport on Saturday afternoon, yelling that they were not getting any updates from MAS and demanding that the Chinese government send military planes to conduct search and rescue efforts.
A distraught woman in her 30s shouted to a mob of journalists: "All we have is a piece of paper saying the same things that you guys already know! We demand the Chinese government to send rescue teams immediately."
Questions were raised about why the airline released the news so late.
MAS put out its first statement at 7.24am. The first wire news report came out at 8.20am.
Adding to the confusion were rumours that started early on Saturday morning, first saying the plane had landed safely in Vietnam, then that it had landed in the southern city of Nanning in China.
Later came reports that it had crashed in the waters off Vietnam.
In Kuala Lumpur, MAS told passengers' next of kin to come to the international airport with their passports to prepare to fly to the crash site, which had still not been identified.
There was no information of a possible bomb or terror attack behind the missing plane, and Malaysia is studying all possibilities, Acting Transport Minister Hishammuddin Hussein told reporters on Saturday.
State-owned Malaysian Air recently announced plans to upgrade its fleet after failing to post a profit in each of the past three years.
The aircraft was 11 years and 10 months old and had fuel to fly to Beijing and beyond, CEO Ahmad Jauhari said. Captain Zaharie Ahmad Shah, 53, and First Officer Fariq Ab. Hamid, 27, were the pilots, according to an airline statement. The captain had 18,365 flying hours and joined the company in 1981, while his first officer had 2,763 hours of flying. - With information from The Straits Times China Bureau.