(CNN) Update at 5:42 a.m. Thursday -- Reports suggesting the missing Malaysia Airlines plane kept flying for four hours after its last reported contact are inaccurate, Malaysia's acting Transportation Minister Hishammuddin Hussein said Thursday.
The report earlier Thursday from the Wall Street Journal said U.S. aviation investigators and national security officials were basing their belief that the missing plane kept flying on data automatically transmitted to the ground from the passenger jet's engines.
The newspaper attributed the information to two unidentified people who were "familiar with the details."
[Original story, posted at 5:32 a.m. Thursday]
Report: Malaysia Airlines Flight 370 kept flying for hours after last contact
(CNN) -- The puzzle over the disappearance of Malaysia Airlines Flight 370 grew even more complex Thursday when a report emerged suggesting the missing plane may have flown on for about four hours after its last reported contact.
The report from the Wall Street Journal said U.S. aviation investigators and national security officials were basing their belief that the missing plane kept flying on data automatically transmitted to the ground from the passenger jet's engines.
The newspaper attributed the information to two unidentified people who were "familiar with the details." CNN was not immediately able to confirm the report.
If the plane did indeed stay in the air for several hours after it lost contact with air traffic controllers early Saturday, the challenge facing investigators and search teams becomes immensely more complicated.
Four more hours in the air could put the plane many hundreds of miles beyond the area currently being searched.
And the new report opens the door to a fresh round of theories about what has become of the plane, which vanished early Saturday while flying over Southeast Asia on its way from Kuala Lumpur to Beijing.
But one aviation industry observer expressed skepticism about the report.
"I find this very, very difficult to believe," Tom Ballantyne, chief correspondent for the magazine Orient Aviation told CNN. "That this aircraft could have flown on for four hours after it disappeared and not have been picked up by someone's radar and not have been seen by anyone, it's almost unbelievable."
The mystery over the fate of the passenger jet, a Boeing 777-200, and the 239 people it was carrying has so far left government officials and aviation experts flummoxed.
Searchers have already been combing a vast area of sea and land for traces of the plane. But so far, with the search well into its sixth day, their efforts have been fruitless.
The Wall Street Journal report said the plane's engines have an onboard monitoring system supplied by their manufacturer, Rolls-Royce PLC. The system "periodically sends bursts of data about engine health, operations and aircraft movements to facilities on the ground," the newspaper said.
Malaysia Airlines sends its engine data live to Rolls-Royce for analysis, the report said, and that data is now being analyzed to figure out the flight path of the missing plane after contact was lost with its transponder, a radio transmitter in the cockpit that communicates with ground radar.
Erin Atan, a spokeswoman for Rolls Royce in Asia, declined to comment on the report Thursday, telling CNN the matter was "an official air accident investigation."
Azharuddin Abdul Rahman, the director general of Malaysia's Department of Civil Aviation, said he was aware of the Wall Street Journal report but couldn't comment further.
Still no trace
As word of the report spread, searchers appeared to draw another blank in the so far frustrating endeavors to find traces of the plane.
Vietnamese and Malaysian planes spotted no sign of debris when they flew over an area of sea that Chinese authorities had flagged as the location of possible remnants of the missing plane, officials said.
China's State Administration for Science, Technology and Industry for National Defense had said satellite images showed "three suspected floating objects" that it described as "a suspected crash site."
The images were captured around 11 a.m. Sunday, the day after the plane went missing, but final versions of them weren't released until Wednesday.
The Chinese agency gave coordinates of 105.63 east longitude, 6.7 north latitude, which would put the objects in waters between Malaysia and southern of Vietnam, near where the plane lost contact with air traffic controllers.
Meanwhile, India is joining the multinational search, dispatching two of its naval ships off the remote Andaman and Nicobar Islands, a military spokesman told CNN on Thursday.
Navy and coastguard aircraft are also expected to be sent toward the Strait of Malacca once "exact coordinates" are received for the search area, Andaman and Nicobar's joint naval command spokesman Harmeet Singh said.
Last known words
Also on Thursday, a Malaysian aviation official told CNN that the last known words from the flight crew of the missing plane were "Alright, good night."
Malaysian civil aviation officer Zulazri Mohd Ahnuar said he couldn't confirm which member of the flight crew sent the message, which was transmitted from the plane back to Malaysian flight controllers as the aircraft transferred into Vietnamese airspace early Saturday.
For the families of those on board the missing plane, the wait for news is tortuous.
Danica Weeks is trying to keep it together for her two young sons, though the possibility of life without husband Paul, who was on the plane, is sometimes overwhelming. She's clinging to hope even though, as Weeks told CNN's Piers Morgan, it's "not looking good."
"Every day, it just seems like it's an eternity, it's an absolute eternity," Weeks said from Australia. "We can only go minute-by-minute ... and hope something comes soon."
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