A long-awaited official report into the disappearance of Flight MH370 gave no new clues Monday about why the Malaysian plane vanished, sparking anger and disappointment among relatives of those on board.
The report from the official investigation team pointed to failings by air traffic controllers and suggested the Malaysia Airlines plane was likely diverted from its flight path manually, rather than due to a mechanical fault.
But it said the Boeing 777 jet, which vanished over four years ago as it flew from Kuala Lumpur to Beijing with 239 people on board, was airworthy and the pilots were in a fit state to fly.
After years of fruitless searching in the world's most enduring aviation mystery, the report offered nothing concrete to grieving relatives of passengers -- most of whom were Chinese -- and crew hoping for some sort of closure.
"The team is unable to determine the real cause for the disappearance of MH370," concluded the largely technical 400-page report.
Relatives who were briefed at the transport ministry before the report's public release expressed anger that there was nothing new in the document, with some storming out of the briefing as frustration boiled over.
"It is so disappointing," said Intan Maizura Othman, whose husband was a steward on MH370. "I am frustrated. There is nothing new in the report.
"Those who gave the briefing from the ministry of transport were not able to give answers as they were not (the ones) who wrote the report."
She said the meeting between relatives and officials descended into a "shouting match" as family members' frustration boiled over.
"Many asked questions," said G. Subramaniam, who lost a son on the flight, but added that "unsatisfactory responses left many angry".
The disappearance of MH370 triggered the largest hunt in aviation history. But no sign of the jet was found in a 120,000-square kilometre (46,000-square mile) Indian Ocean search zone and the Australian-led hunt was suspended in January last year.
US exploration firm Ocean Infinity resumed the search in a different location at the start of this year on a "no find, no fee" basis, using high-tech drones to scour the seabed. But that search was also called off after failing to find anything.
Only three confirmed fragments of MH370 have been found, all of them on western Indian Ocean shores, including a two-metre wing part known as a flaperon.
Malaysia's new government, which took power in May, has said the hunt could be resumed but only if new evidence comes to light and officials have seemed keen to draw under a line the tragedy.
One area that came in for criticism in the report by the 19-member investigation team, which included foreign investigators, was air traffic control.
It said both Malaysian air traffic control and their Vietnamese counterparts failed to act properly when the Boeing jet passed from Malaysian to Vietnamese airspace and disappeared from radars.
Air traffic controllers did not initiate emergency procedures in a timely fashion, delaying the start of the search and rescue operation, it said.
However it played down concerns about the pilot and first officer, saying neither appeared to have suffered difficulties in their personal lives that could have affected their ability to fly.
It also said the plane was airworthy and did not have major technical issues. This however meant that the plane's change of course "was likely made while the aircraft was under manual control and not the autopilot", the report said.
Intervention by a third party could not be ruled out, it said, but also added there was no evidence to suggest the plane was flown by anyone other than the pilots.
The report also dismissed one conspiracy theory about the plane's disappearance -- that it was taken over remotely to foil a hijacking, saying there was no evidence to support this.
Putrajaya, Malaysia | AFP