Malaysia said Monday the passenger jet which went missing more than two weeks ago crashed in the Indian Ocean, but shed no light on the mystery of why it veered from its intended course.
Prime Minister Najib Razak said new satellite analysis of Malaysia Airlines Flight MH370's path placed its last position in remote waters off Australia's west coast, and far from any landing sites.
The sombre announcement on the fate of the plane ended 17 days of agonising uncertainty for relatives of those on board -- two thirds of them Chinese.
"It is therefore with deep sadness and regret that I must inform you that, according to this new data, flight MH370 ended in the southern Indian Ocean," Najib said.
He said the flag carrier had already spoken to the families of the passengers and crew aboard the jet which disappeared on March 8 on an overnight flight from Kuala Lumpur to Beijing.
"For them, the past few weeks have been heartbreaking; I know this news must be harder still."
Najib said he had been briefed by representatives from Britain's Air Accidents Investigation Branch, which relayed further analysis of satellite data by British company Inmarsat.
'No words to ease pain'
The airline, in a statement sent to families, said "we have to assume" the plane was lost. "Our prayers go out to all the loved ones of the 226 passengers and of our 13 friends and colleagues at this enormously painful time," it said.
"We know there are no words that we or anyone else can say which can ease your pain." The airline said the multinational search, which is scouring a stretch of the forbidding Indian Ocean to find any debris, would continue "as we seek answers to the questions which remain"
Malaysia believes the plane was deliberately diverted by someone on board. But the absence of firm evidence has fuelled intense speculation and conspiracy theories, and tormented the families of the missing.
Leading theories include a hijacking, pilot sabotage, or a sudden mid-air crisis that incapacitated the flight crew and left the plane to fly on auto-pilot until it ran out of fuel.
MH370 last made contact over the South China Sea halfway between Malaysia and Vietnam. For reasons unknown, it backtracked over the Malaysian peninsula and then flew on for hours.
The search swung deep into the Indian Ocean last week after initial satellite images depicted large floating objects there.
Hopes of a resolution to the mystery rose after a weekend in which an Australian aircraft spotted a wooden pallet, strapping and other debris, and French and Chinese satellite information indicated more floating objects.
An Australian-led multinational air and sea search has been scouring the vast ocean and there were two separate sightings Wednesday of possible debris from the plane.
Crew members of an Australian P-3 Orion plane reported seeing two objects, Australian Prime Minister Tony Abbott told parliament.
Australian officials said they were different to pieces seen by a Chinese plane earlier in the day. The Australian naval ship HMAS Success, equipped with a crane, was in the area, about 2,500 kilometres (1,562 miles) southwest of Perth, and will attempt to recover the objects.
Abbott cautioned that it was not known whether the objects came from the missing Boeing 777. "Nevertheless we are hopeful that we can recover these objects soon and they will take us a step closer to resolving this tragic mystery," he said.
Hunt for 'black box'
The US Navy has added to the sense of an approaching denouement, ordering a specialised device sent to the region to help find the "black box" flight and cockpit voice data -- crucial in determining what happened to the plane.
The high-tech device can locate black boxes as deep as 20,000 feet (6,060 metres), the US Seventh Fleet said in a statement. The search area ranges from 3,000-4,000 metres deep.
The 30-day signal from the black box is due to fail in less than two weeks.
The Australian Maritime Safety Authority said the search grew to 10 aircraft on Monday with the inclusion of two Chinese military aircraft joining Australian, US, and Japanese planes.
China has also dispatched seven ships, adding to British and Australian naval vessels involved.
If a crash is confirmed, recovering the black box will be even more difficult than the case of the Air France jet that went down in the Atlantic in 2009, said Charitha Pattiaratchi, an oceanographer at the University of Western Australia.
"We have to remember that Air France 447 took two years to find and this is a more challenging region where the environment is much, much harsher. There are bigger waves and it's windier," he said.
As part of an investigation into the crash, Malaysian Transport Minister Hishammuddin Hussein said police have interviewed more than 100 people, including families of both the pilot and co-pilot.
Malaysia Airlines said Monday that 27-year-old co-pilot Fariq Abdul Hamid was flying the Boeing 777 for the first time without a so-called "check co-pilot" looking over his shoulder.