The biggest clue so far is traces of oil that a Vietnamese plane spotted while flying over the search area. The oil slicks are between 6 and 9 miles long and are suspected to be from the missing plane, the Vietnam government's official news agency reported. The traces of oil were found about 90 miles south of Tho Chu Island, the report said.
The area of focus has been in the South China Sea, where the Malaysian airspace and Vietnamese airspace meet.
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For instance, after the airline released a manifest, Austria denied that one of its citizens was onboard the flight as the list stated. The Austrian citizen was safe and sound, and his passport had been stolen two years ago, Austrian Foreign Ministry spokesman Martin Weiss told CNN.
Similarly, Italy's foreign ministry confirmed that no Italians were onboard MH370, even though an Italian was listed on the manifest. Malaysian officials said they were aware of reports that the Italian's passport was also stolen, but had not confirmed it.