The Malaysian government on Thursday rejected reports that automatically-transmitted engine data shows that a missing passenger plane may have flown for another four hours after the last confirmed location.
Flight MH370 vanished an hour after taking off from Kuala Lumpur for Beijing on 8 March with 239 people on board, including two New Zealanders. No distress signal or message was sent.
Officials have denied reports that the aircraft had continued to send technical data and said there was no evidence that it flew for hours after losing contact with air traffic controllers.
The Wall Street Journal reported that data continued to be automatically downloaded from the plane's engines for four hours after tracking of its transponder stopped.
Malaysia's Acting Transport Minister Hishammuddin Hussein denied that report, saying the last engine data was sent nearly half an hour before the last confirmed contact with the plane.
"News reports suggesting that the aircraft may have continued flying for some time after last contact - those reports are inaccurate. As far as both Rolls-Royce and Boeing are concerned, those reports are inaccurate. The last (data) transmission from the aircraft was at 1.07am (local time) which indicated that everything was normal."
Malaysia Airlines said the plane passed all its maintenance checks in February this year.
Planes on Thursday scanned an area of sea where Chinese satellite images had shown what could be debris, but found no sign of the airliner.
Mr Hishammuddin said the images were not confirmed to be connected to the plane and were made public accidentally. "The Chinese government neither authorised nor endorsed (putting it on a website)."
It was the latest in a series of false signals for the Boeing 777-200ER, adding to the confusion and agony of the relatives of the passengers.
As frustration mounted over the failure to find any trace of the plane, China heaped pressure on Malaysia to improve co-ordination in the search, Reuters reported. Around two-thirds of the people aboard the lost plane were Chinese.