As the hunt for the missing Malaysian Air jumbo jet gained momentum Sunday in the South China Sea and Malaysian intelligence agencies were investigating potential terrorism, hopes were all but gone for the 239 passengers and crew.
Military ships and aircraft from half a dozen nations continued to pour into the area, searching for the Boeing 777 that vanished suddenly and without warning early Saturday morning, two hours after a scheduled six-hour flight from Kuala Lumpur to Beijing.
A search found two large oil slicks off the southern tip of Vietnam Saturday, but an overnight search that extended into Sunday afternoon yielded no signs of wreckage.
Meanwhile, a Malaysian Air Force official said Sunday the flight may have tried to return to Kuala Lumpur,
Air force chief Rodzali Daud said military radar indicated that Flight MH370 "may have made a turn back," but did not say how far it got. "We are trying to make sense of this," Daud said.
As the hunt for the missing Malaysian Air jumbo jet gained momentum Sunday in the South China Sea and Malaysian intelligence agencies were investigating potential terrorism, hopes were all but gone for the 239 passengers and crew.
Military ships and aircraft from a half dozen nations continued searching for the Boeing 777 that vanished without warning early Saturday morning, two hours after a scheduled six-hour flight from Kuala Lumpur to Beijing. The U.S. Navy has provided the USS Pinckney, a guided missile destroyer that carries two MH-60R helicopters, and a P-3C Orion with long-range search, radar and communications capabilities.
"Our thoughts and prayers go out to all of those affected by this tragic event," the Navy said in a statement.
Two large oil slicks were found off the southern tip of Vietnam Saturday, but no signs of wreckage had been found Sunday.
Ignatius Ong, a representative of Malaysia Airlines, said at a press conference in Beijing that search and rescue efforts are "still unable to detect the whereabouts of the missing flight."
The airline has been telling relatives "to expect the worst," Ong said.
When the plane is located, the airline will set up a command center either in Malaysia's Kota Bharu, or in Vietnam, depending on its location. A response control center will be activated as close as possible to the incident area, he said.
The airline plans to send two family members for each missing passenger to Kuala Lumpur, or another destination if closer to the plane's location. The airline is working with Chinese authorities to get passports for relatives who lack them, and with the Malaysian Embassy in Beijing to get entry visas for Malaysia.
The first flight will be Monday for relatives who want to travel to Kuala Lumpur, and arrangements will continue for those who decide to wait in Beijing, Ong said.
Speculation on the cause of the crash ranged from catastrophic mechanical failure to terrorism, fanned by a flight manifest which showed two passengers had flown with stolen passports.
Malaysian Transport Minister Hishammuddin Hussein said authorities are looking at four possible cases of suspect identities and had contacted the FBI and other intelligence agencies. "We do not want to target only the four; we are investigating the whole passenger manifest. We are looking at all possibilities."
Two names on the flight manifest matched names on stolen European passports.
The Italian Foreign Ministry said Luigi Maraldi, an Italian national, was traveling in Thailand and contacted family after the Malaysian Air flight went missing. Maraldi reported a stolen passport last August. Austrian officials said the name Christian Kozel listed on the manifest matched the name of an Austrian man whose passport stolen in 2012.
Both names were ticketed to continue from Beijing to destinations in Europe and thus did not need visas for China.
U.S.: Reviewing possible terror links
The 11-year-old jet was last inspected 10 days ago and found in "proper condition," airline officials said. The lack of a distress signal from the pilots "suggests something very sudden and very violent happened," said William Waldock, who teaches accident investigation at Embry-Riddle Aeronautical University in Prescott, Ariz.
Weather was not believed to be a factor. Light rain and snow was falling over South and Central China, but it was well below the aircraft's last known, 35,000-foot altitude.
However the flight disappeared, the mother of Philip Wood - one of three Americans on the flight - was resigned that he was gone. "You want to know how it feels to lose a son at the age of 50? It's devastating,'' Sandra Wood said. She saw her son, an IBM executive who worked in Malaysia, a week ago.
Freescale Semiconductor, an Austin-based tech company, said 20 employees from China and Malaysia were aboard. "Our thoughts and prayers are with those affected by this tragic event," said CEO Gregg Lowe.
MORE: Details emerge about American, other passengers
Search efforts were concentrated where two oil slicks, each 6 to 9 miles long, were found by about 80 miles south of the island of Tho Chu in the Gulf of Thailand by Vietnamese military aircraft Saturday.
Malaysia sent nine planes and 15 ships to search waters between Malaysia and Vietnam. The Philippines dispatched three Navy ships and a surveillance plane. China sent two ships. A U.S. Navy destroyer equipped with two helicopers is also assisting the operation.
The plane was two hours into its flight when Subang Air Traffic Control lost contact at 2:40 a.m. local time (1:40 p.m. Friday ET). It was scheduled to land in Beijing at 6:30 a.m. local time. The last radar signal was received as the aircraft approached Vietnam airspace near the Ca Mau province.
The twin-engine jet was carrying 227 passengers and 12 crew.
They're from 14 countries, including 153 from China, 38 from Malaysia, seven from Indonesia, six from Australia, five from India, three from France, two each from New Zealand, Ukraine and Canada and sole travelers from Russia, Italy, Taiwan, Austria and the Netherlands. Besides Woods, the other Americans on the manifest are young children - Nicole Meng, 4, and Yan Zhang, 2.(USA Today)