EMOTIONAL families marked the first anniversary of the disappearance of Flight MH370 yesterday as a new report said the battery for its black box locator beacon had expired more than a year before the plane vanished, but shed no new light on the cause of the disaster.
Prime Minister Najib Razak said his nation remained committed to the so-far fruitless hunt for the Malaysia Airlines flight, which is believed to have crashed in the southern Indian Ocean, and was hopeful it would be found.
Next of kin, many of whom have criticised Malaysia's handling of the disaster, held ceremonies in Kuala Lumpur and Beijing to remember the missing and urge the authorities not to abandon the expensive and arduous search.
"The only answer I want is where is the plane, then only will we know," said Jacquita Gonzales, wife of the flight's cabin crew supervisor, Patrick Gomes. "The whole world has heard what he (Mr Najib) has said, so they can't go back on their word."
A report by an international investigative team released yesterday raised no red flags relating to the crew or the aircraft's condition to indicate any cause for the disappearance.
But it said the battery powering the underwater locator beacon on the plane's flight data recorder had been due to expire in December 2012.
Although the battery on the plane's cockpit voice recorder was up to date, this could have potentially contributed to the failure to find the plane so far, said Gerry Soejatman, a Jakarta-based aviation consultant.
"My major worry is that (search vessels) may have gone over the aircraft but not heard the pings because of this," said Mr Soejatman, who added that the report otherwise largely restated what is already known about MH370.
A year-long hunt in the deep ocean at least 1,600km off Australia's western coast, where satellite data indicated the Boeing 777 crashed, has so far yielded no sign of the plane.
"Together with our international partners, we have followed the little evidence that exists," Mr Najib said in a statement. "Malaysia remains committed to the search, and (is) hopeful that MH370 will be found."
The plane inexplicably veered from its Kuala Lumpur-Beijing route on March 8 last year with 239 passengers and crew members aboard.
Relatives and friends of the missing held an emotional public remembrance in Kuala Lumpur that included prayers and live video links with other next of kin around the world.
A temporary wall erected for the occasion contained scrawled messages such as "Never give up hope" and "I miss you so much brother and sister, please come back".
Grace Subathirai said: "My mother was on MH370. It has been a year so far. It has been a most painful year for many of us, a never-ending battle.
"My mother was my world, everything to me," she added, her voice breaking.
In Beijing, relatives who have bitterly criticised Malaysia's national carrier and government for their handling of the crisis gathered amid a heavy police presence to mark the anniversary.
Shouting slogans including "Fight to the end" and "Malaysian government - apologise to us!", they mounted a small protest near the Malaysian Embassy, which was blocked by dozens of uniformed security staff.
Yesterday's report said investigators had probed a range of issues including the captain and co-pilot's personal, psychological and financial profiles, and the backgrounds of the 10 cabin crew members.
Although suspicion had fallen on the cockpit crew of pilot Zaharie Ahmad Shah and his co-pilot Fariq Abdul Hamid, the report found no evidence suggesting their involvement.
"There were no behavioural signs of social isolation, change in habits or interest, self-neglect, drug or alcohol abuse of the captain, first officer and the cabin crew," it said.
Earlier yesterday, Australian Prime Minister Tony Abbott said that while the current search area is expected to be covered in May, the operation could be extended further "as long as there are reasonable leads".