Captain Zaharie Shah has been identified as the chief suspect in the plane's disappearance - if it was due to human interference - according to a media report.
The Times newspaper claims to have obtained access to the initial results of a criminal inquiry shared with foreign governments and investigators.
The report states that Zaharie had made no plans or commitments for the future, in contrast with co-pilot Fariq Hamid and the rest of the crew, according to the Times.
The paper further claims that investigators uncovered a deleted file on Zaharie's flight simulator showing a flight path to the southern Indian Ocean, and a landing on a small island, although details of the simulated flights were not reported.
A massive aerial and underwater search for MH370, which had 239 people onboard when it diverted from its Kuala Lumpur to Beijing flight path on March 8, has failed to find any sign of the plane.
Scientists from British satellite operator Inmarsat told the BBC earlier this week that the search had yet to target the most likely crash site, or "hotspot", after becoming diverted by pings thought at the time to have originated from the plane's black boxes.
Until now, the most intensive search had been with a mini-sub in the area where the pings were detected. The area has now been ruled out as the final resting place of MH370. The source of the noises is unknown.
JACC said last Friday that the revised search zone, based on an intensive study of satellite communications from the jet and other data, would be announced by the end of the month.
It said the Fugro Equator was now working in this zone.
"Located along the seventh arc, that area is consistent with provisional analysis of satellite and other data that is being used to determine the future search area," it said.
Australian officials announced earlier this week that a survey of the sea bed, as yet mostly unmapped and crucial to the success of the underwater search, had resumed.
The two ships -- Fugro Equator and Zhu Kezhen -- will survey an area up to 6,000 metres (20,000 feet) deep and covering up to 60,000 square kilometres before an a contractor begins an intensive undersea probe looking for debris.