The new Chinese reports of the satellite images came after several days of sometimes confusing and conflicting statements from Malaysian officials.
Earlier Wednesday, the Malaysian military officially disclosed why it was searching on both sides of country: A review of military radar records showed what might have been the plane turning back and crossing westward into the Strait of Malacca.
That would conflict with the latest images on the Chinese website.
For now, authorities said the international search effort would stay focused on the South China Sea and the strait leading toward the Andaman Sea.
Chinese impatience has grown.
"There's too much information and confusion right now. It is very hard for us to decide whether a given piece of information is accurate," Chinese Foreign Ministry spokesman Qin Gang said in Beijing. "We will not give it up as long as there's still a shred of hope."
"We have nothing to hide," said Malaysian Defense Minister Hishammuddin Hussein. "There is only confusion if you want to see confusion."
Flight MH370 disappeared from civilian radar screens at 1:30 a.m. Saturday at an altitude of about 35,000 feet above the Gulf of Thailand between Malaysia and southern Vietnam. It sent no distress signals or any indication it was experiencing problems.
The amount of time needed to find aircraft that go down over the ocean can vary widely. Planes that crash into relatively shallow areas, like the waters off Vietnam where the Malaysian jet is missing, are far easier to locate and recover than those that plunge deep into undersea canyons or mountain ranges.
By contrast, much of the Gulf of Thailand is less than 300 feet (91 meters) deep.
The Malaysian government said it had asked India to join in the search near the Andaman Sea, suggesting the jetliner might have reached those waters after crossing into the Strait of Malacca, some 400 kilometers from the flight's last-known coordinates.