The mystery of Malaysian Airlines flight MH370 remains unsolved, as a long-awaited report fails to deliver answers for grief-stricken families more than four years after the tragedy.

The Malaysian government’s Safety Investigation Report was handed down on Monday, with lead investigator Kok Soo Chon delivering his findings to an international press pack in Putrajaya, outside Kuala Lumpur.

The report brought little closure for victims’ families, with investigators ultimately “unable to determine the real cause for the disappearance of MH370”.

Initially billed as the Malaysian government’s ‘final’ report on the ill-fated Malaysia Airlines flight, which disappeared en route from Kuala Lumpur to Beijing on March 8, 2014, Mr Kok instead told reporters that “it would be too presumptuous of us to say this is the final report”.

Lead investigator Kok Soo Chon addresses media. Photo: Getty

“The wreckage has not been found. No victims have been found. How could we call it a final report?” Mr Kok said.

“This report is released at this point in time because we don’t know if there will be another search or another team.

“There has to be some form of closure, albeit unsatisfactory to a lot of people.”

‘Cannot rule out interference by a third party’

Despite speculation, investigators concluded that MH370’s pilot and first officer were not responsible for the tragedy.

“We have examined the pilot and the first officer, and are satisfied with their background, training, mental health and state,” Mr Kok said.

“We are not of the opinion that it could have been an event committed by the pilot. But we cannot deny the fact that there was an air turn-back, and that the systems were manually turned off with intent or otherwise.”

The Malaysian government’s long-awaited report provided few answers. Photo: Getty

Investigators used civilian and military radar data to establish that MH370 diverted from its flight course, and then turned back while under manual control.

Despite appearing to absolve the pilot, investigators also confirmed that the aircraft’s auto-pilot system was deliberately disengaged in order for the turn-back to occur.

According to Mr Kok, there is “one possibility could account for all this”.

“We cannot establish that the aircraft was flown by anyone other than the pilot, but cannot exclude unlawful interference by a third party,” Mr Kok said.

The report also highlighted a number of critical mistakes made by air traffic controllers in both Kuala Lumpur, Malaysia and Ho Chi Minh City, Vietnam.

A series of errors began when traffic controllers in Malaysia mistakenly transferred MH370 to air traffic controllers in Ho Chi Minh three minutes before scheduled, but failed to inform their counterparts.

By the time air traffic controllers in Ho Chi Minh realised the mistake, the aircraft had vanished.

Air traffic controllers also failed to follow proper emergency protocol, and delayed alerting the Malaysian airforce, Mr Kok said.

Outrage from victims’ families

The report offered little solace for angry, grief-stricken family members of the 239 people on board the MH370, which included six Australians.

Families weep after receiving final report on MH370. “There’s no conclusion” pic.twitter.com/u40tuFuzM1

— David Lipson (@davidlipson) July 30, 2018

“They say they are not the search team, then who are you guys? Where’s the people who do the research? We want to talk to them,” one family member told reporters in Kuala Lumpur.

“How can you guys expect us to believe everything in there? They are not the research teams. There’s no conclusion. There’s no answer.”

Voice370, a group representing families of the passengers and crew on board MH370, described the report as “simply unacceptable”.

“Four years four months 22 days, 1605 days of roller coaster, families still have no closure with the release of the latest 495 pages safety investigation report,” the group said on Facebook.

“Simply unacceptable as a ‘final’ report. How can we prevent another MH370 incident in future?”

Experts,  families call for search to continue 

Aviation experts and victims’ families have called for the search for MH370 to go on.

“The search should continue. I think it’s very unfortunate that the search has been abandoned twice,” Monash University aviation expert Professor Greg Bamber told The New Daily.

It is impossible for investigators to provide “any definitive answers” until the wreckage of the plane or its black boxes are recovered and the search should continue for “as long as it takes”, Professor Bamber said.

“The ocean is very deep and difficult terrain. It’s more difficult than looking for a needle in the haystack. But let’s continue with the search and find the evidence in the interests of aviation safety in the future,” he said.

The four-year search for MH370 ended in May after Ocean Infinity failed to locate the plane while scouring 125,000 square kilometres of the Indian Ocean.

Malaysia had signed a “no find, no fee” deal with American company Ocean Infinity to resume the hunt after the official search – led by Australia, Malaysia and China – was called off in early 2017.

There has been speculation Ocean Infinity could resume the search, as it remains in waters off the Western Australian coast doing work for Woodside Energy.

Danica Weeks, whose husband Paul was on board MH370, also called for the search to continue.

“They need to keep searching – that’s a given. I understand that without new information, you’re throwing the dice and hoping it’s there,” she said.

“It’s a matter of elimination. It’s got to be somewhere.

“They can’t just push it under the carpet and say ‘That’s it’.”

-with AAP