The Malaysian transport minister on Thursday dismissed claims that the missing Malaysia Airlines aircraft may have flown on for about four hours past the time it disappeared off tracking systems.
The Wall Street Journal reported Thursday that the plane, and the 239 people on board, could have flown on for an additional distance of about 2,200 miles (3,500 km), potentially reaching the border of Pakistan or as far as destinations in the Indian Ocean or Arabian Sea. The paper cited two people familiar with the details.
However, Malaysia's Transport Minister Seri Hishammuddin said at a news conference that this report was wrong and that their search efforts had always been focused on the South China Sea. CNN also reported, citing a "senior aviation source," that there was no evidence to suggest the plane kept flying for four hours after disappearing off radar.
The last definitive sighting of the aircraft on civilian radar screens came shortly before 1:30 a.m. on Saturday, less than an hour after taking off from Kuala Lumpur, as it flew northeast across the mouth of the Gulf of Thailand bound for Beijing.
Malaysian Airlines' CEO told a press conference Thursday that the last data transmission from the plane was recorded about 30 minutes after take-off. Ahmad Jauhari Yahya also said that and did not receive any further data from the missing plane.
No traces of the Boeing aircraft travelling to Beijing, China's capital city, have been found even as a multinational search effort has extended its search area.
Responding to criticisms of the Malaysian authorities' investigation in to the missing plane, Hishammuddin emphasized that the situation was "unprecedented," adding: "We are devoting all our energies to the task at hand, and I want to be very clear: Our focus has been on finding the aircraft, we have not done anything that could jeopardize this search effort."
Still, the frustration with the fruitless six-day search for the plane has lead to numerous leads emerging in an attempt to provide clues on where the plane might be.
U.S. counterterrorism officials are pursuing the possibility that a pilot or someone else on board the plane may have diverted it toward an undisclosed location after intentionally turning off the jetliner's transponders to avoid radar detection, the Wall Street Journal reported, said citing one person tracking the probe.
Transport Minister Hishammuddin said that reports that the homes of the missing airplane's missing crew had been searched by the police were untrue and the pilots were not being investigated by authorities.
Hishammuddin also announced that satellite imagery of possible debris issued by Chinese authorities was wrongly issued; reading out a statement from China confirming it was a mistake. Satellite images of what could be debris from Flight MH370 were released by a Chinese government agency late Wednesday.
(Read more: Timeline of flight MH370)
According to Chinese media, the satellite images showed "three suspected floating objects" of various sizes. The largest one was estimated to be roughly 22 meters by 24 meters in size.
Malaysia's civil aviation chief had already said on Thursday that there were no signs of the missing plane at the location where Chinese satellite images have shown what may have been debris.
(Read more: Lack of MH370 news frustrates distraught relatives)
"Current, winds and sea state have an enormous effect on debris - because of that the search area grows by the hour," Commander William J. Marks, U.S. 7th Fleet Public Affairs Officer, told CNBC by email. "Pinckney and Kidd are still in the Gulf of Thailand right now, however we are looking at follow-on plans for the next 24-72 hours and that could change," he added, referring to the U.S. destroyers assisting in the search effort.
Holding out hope
Speaking at a news conference on the final day of China's annual meeting of parliament, Premier Li Keqiang said China was was waiting for even the "slightest piece of good news" on the missing plane.
"As long as there is a glimmer of hope, we will not stop searching for the plane," he said, adding that there are currently eight Chinese vessels involved in the search operation with one more on its way. "I had a telephone conversation yesterday with a captain of one of the Chinese vessels in the search operations and we are looking very closely at suspected clues shown on satellite images."
Gregg Feith, a former senior air safety investigator with the National Transportation Safety Board told CNBC more resources should be sent to verify the Chinese satellite images.
"It's new information by the Chinese saying basically we believe this is part of the missing airplane and another source saying we don't want anything to do with this," he said. "You've now stirred up the pot, you better go out and check it so you can say with certainty whether this is part of the wreckage or not."
The area of search for the missing aircraft has been expanded to 27,000 nautical square miles covering the South China Sea and Strait of Malacca, with a total of 12 countries participating in the operation, Malaysian authorities said late Wednesday.
There have been numerous reports as to what may have happened to the Malaysia Airlines plane, with speculation including possible sabotage, hijacking and technical problems. MH370 was flying in good weather conditions and disappeared without a distress call – unusual for a modern jetliner.
NBC News reported Wednesday that U.S. intelligence satellites detected no signs of an explosion around the time the plane went missing, which one official called "vexing."
Flight codes retired
Malaysia Airlines said on Thursday that as a mark of respect to the passengers and crew of MH370, the flight codes MH370 and MH371 will be retired from the airlines' Kuala Lumpur Beijing-Kuala Lumpur route.
"There are no changes to the frequency of our services and we will continue to operate double daily services to Beijing," Malaysia Airlines said in a statement. "Our thoughts and prayers remain with the families of our colleagues and passengers of MH370."
- Reuters contributed to this report.
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