Vietnamese air force planes on Saturday spotted two large oil slicks close to where a Malaysia Airlines Boeing 777 went missing earlier in the day, the first sign that the aircraft carrying 239 people had crashed.
The air force planes were part of a multinational search operation launched after Flight MH370 fell off radar screens less than an hour after it took off from Kuala Lumpur for Beijing early Saturday morning.
The oil slicks were spotted late Saturday off the southern tip of Vietnam and were each between 10 kilometers (6 miles) and 15 kilometers (9 miles) long, the Vietnamese government said in a statement. There was no confirmation that the slicks were related to the missing plane, but the statement said they were consistent with the kinds that would be produced by the two fuel tanks of a crashed jetliner.
Two-thirds of the missing plane's passengers were from China, while others were from elsewhere in Asia, North America and Europe.
Malaysia Airlines CEO Ahmad Jauhari Yahya said there was no indication that the pilots had sent a distress signal, suggesting that whatever happened to the plane occurred quickly and possibly catastrophically.
Asked whether terrorism was suspected, Malaysian Prime Minister Najib Razak said, "We are looking at all possibilities, but it is too early to make any conclusive remarks."
Foreign ministry officials in Italy and Austria said the names of two nationals from those countries listed on the flight's manifest matched passports reported stolen in Thailand.
Italy's Foreign Ministry said the Italian man who was listed as being a passenger, Luigi Maraldi, was traveling in Thailand and was not aboard the plane. It said he reported his passport stolen last August.
Austria's Foreign Ministry confirmed that a name listed on the manifest matched an Austrian passport reported stolen two years ago in Thailand. It said the Austrian was not on the plane, but would not confirm the person's identity.