The hunt had initially focused on the South China Sea but has shifted dramatically given the absence of any findings, and following the indications the plane altered course.
India's navy said it was doubling, at Malaysia's behest, the number of ships and planes it had deployed to search the Indian Ocean waters around its remote Andaman and Nicobar islands.
The six vessels and five planes were concentrating on an area "designated" by the Malaysian navy in the southern region of the Andaman Sea, naval spokesman D.K. Sharma told AFP. Close to 60 ships and 50 aircraft from 13 countries have been deployed across the entire search zone since MH370 went missing.
Reports of Altered Flight Path
For distraught relatives of the passengers and crew, the expanded search offered no immediate relief from the anguished frustration of a week tainted by false leads and rumors.
"Right now, anything is possible," said a middle-aged Chinese woman in Beijing who had a relative on the flight and complained of a lack of information. "We keep hoping there will be some good news, but it's not going well."
Malaysian Transport and Defense Minister Hishammuddin Hussein on Friday repeatedly refused to comment on what he termed "unverified" information, as reports of an altered flight path mounted.
Multiple US media reports also had cited unidentified officials as saying a satellite continued to detect the plane's automated communication system for hours after radar contact was lost. The New York Times reported that Malaysian military radar data had shown the airliner altering course at least twice and changing altitude -- sometimes erratically.
Hishammuddin confirmed the expansion of search operations in the Indian Ocean. The widening of the geographical search parameters poses enormous logistical challenges for wreckage identification and recovery. The vast Indian Ocean has an average depth of nearly 3,900 meters (12,800 feet) and any debris would have been widely dispersed by currents after a week.
"Wind and sea conditions are definitely going to play a very big part if there is wreckage, and if it happens to be in the Indian Ocean. It is an immense area," said Greg Waldron, Asia managing editor for aviation industry magazine FlightGlobal.
If it does turn out that Malaysian military radar tracked the missing aircraft, there will be questions as to why the air force was not sent to investigate a large plane flying with no transponders over a strategically sensitive region.
The plane has one of the best safety records of any jet, and the airline also has a solid record.