Malaysia plane families' fears and hopes

New revelations about a missing Malaysia Airlines plane have left anguished relatives contemplating the prospect those on board endured a terrifying hijack ordeal.

But while the disclosures have led to increased speculation of a terror plot or pilot suicide, for some they offer a glimmer of hope - that flight MH370 may somehow have landed safely and their loved ones are still alive.

For relatives of Bob and Cathy Lawton, a missing Australian couple, the possibility of a terrifying drawn-out fate reflects their deepest fears.

"That's one of the worst things I could have hoped for," Bob's brother David Lawton told News Limited newspapers on Sunday.

"Even if they are alive, what did they have to put up with?"

Prime Minister Najib Razak declined to use the word hijack when he briefed the press on Saturday but said new data suggested a "deliberate action" to divert the plane.

The Boeing 777's communications appear to have been switched off manually before the jet with 239 people on board veered westward and flew for hours.

For relatives in China, which had 153 citizens on the flight, the investigators' breakthrough has just brought more distress and frustration.

"We are experiencing an ordeal. We are still waiting for (more information)," said one tearful man emerging from a meeting between Malaysia Airlines and relatives in Beijing on Sunday morning.

"We are extremely anxious. A long time has passed and they don't disclose (more) information," he said.

Malaysian authorities have been severely criticised for failing to share information or for issuing contradictory statements.

China's media made fresh criticism on Sunday, saying Malaysia had "squandered" precious time and resources by releasing the dramatic information on the plane's fate a full week after it vanished.

Yet for some the new evidence brought relief - and a reason for hope.

"Our family is relieved that there's an official statement from the Malaysian government, delivered by the Malaysian prime minister, that there's a possibility that the aircraft might have been hijacked," said Indonesian Santi, 42, who goes by one name.

Her brother Sugianto Lo was on the flight with his wife Vinny Chynthya.

"There have been too many speculations about the missing plane so this official statement has helped to quash some of them.

"At least it gives us hope that our loved ones are still safe. We really hope that the various governments will help to look for the plane," she said.

While the theory the plane landed somewhere and has remained hidden is seen as highly improbable by experts, most do not discount it as impossible.

Malaysian Subramaniam Gurusamy, 60, whose 34-year-old son Puspanathan Gurusamy was on board, refused to believe the worst.

"I am praying every day for divine help. I will not lose hope. I want to hear my son cry out 'Father!" he said.