Malaysia vehemently denies mishandling crucial information on the fate of missing Malaysia Airlines flight 370, but questions persist as to whether early missteps and secrecy contributed to the disappearance of a huge passenger plane on a clear night.

Foreign media reports, especially those in China's state media, have accused the Malaysian authorities of incompetence, misleading the public and exacerbating the suffering of the relatives of those missing.

Two-thirds of the passengers on the Boeing-777 that effectively vanished 11 days ago were Chinese nationals.

The Malaysian government has pleaded for patience and understanding, arguing it has no choice but to hold back information that has not been painstakingly verified.

Critics say the lack of progress in the search for the plane is symptomatic of an inefficient ruling elite unused to tough questioning.

"The Malaysian leadership is not used to being held to account on anything," Michael Barr, an Asian politics expert at Flinders University in Australia, told AFP.

"They are more used to controlling the press and silencing critics," he said.

The authoritarian Barisan Nasional government has been in power since independence from colonial rulers Britain in 1957.

It has overseen decades of growth that have seen Malaysia emerge as Southeast Asia's third largest economy, posting a healthy GDP expansion of 4.7 percent last year.

But analysts say unchallenged power has also bred apathy and inefficiency.

The stumbles over the missing plane search show that the government "lacks the ability to handle many technical matters with assurance and to communicate its purposes globally with clarity and agility," said Clive Kessler, emeritus professor of sociology and anthropology at the University of New South Wales.

Malaysian opposition leader Anwar Ibrahim who, along with right groups, has routinely accused the government of civil liberties abuses and corruption, was even more scathing.

"The mysterious disappearance of MH370 reflects not only an incompetent regime ruling the country but an irresponsible government," Anwar told AFP.

He was speaking in response to speculation that the captain of this airliner -- a member of Anwar's party -- may have been driven by political motives to sabotage the plane.

Anwar said he was "disgusted" by what he saw as an attempt to smear the pilot, Zaharie Ahmad Shah, and somehow implicate the opposition leadership in the March 8 disappearance of Malaysia Airlines Flight 370.

- Military gaffe? -

Among the most glaring questions being asked is why the Malaysian military failed to react to the aircraft re-routing across the Malay peninsula shortly after it dropped out of civilian radar contact.

Malaysian officials said military radars had picked up the plane -- travelling unidentified on an unscheduled route -- but no action was taken as it did not appear "hostile".

They also said it had taken time to verify that the radar blip being tracked was indeed MH370 because its main automated signalling systems had been disabled.

The military "clearly knew more about what happened to MH370 than any other Malaysian agency," said David Learmount, safety and operations editor of aviation industry magazine Flightglobal.

"But the authorities do not seem to have tapped into this expertise, and the military may have been slow to volunteer it."

Daily press briefings by government, aviation and security officials have been tainted by contradictory statements that have created confusion and frustration.

In the latest example on Monday, Malaysia Airlines CEO Ahmad Jauhari Yahya revealed information on the crucial sequence of events in the plane's cockpit before it veered off course that totally contradicted the version provided the previous day by Transport Minister Hishammuddin Hussein.

- Angry relatives -

Earlier examples included discrepancies about the number and ethnicities of passengers using stolen passports, and whether some passengers booked on the flight had failed to board or not.

At a meeting with airline officials in Beijing on Monday, relatives of the Chinese passengers accused Prime Minister Najib Razak and his ministers of "talking nonsense" and intentionally masking negative details about the search effort.

Premier Li Keqiang also entered the fray, asking Najib to provide more details about the missing flight "in a timely, accurate and comprehensive manner."

Cleary annoyed by the constant criticism, Hishammuddin, a cousin of Najib's, reacted angrily when a foreign journalist suggested Malaysia should apologise for its handling of the crisis.

"I think it is very irresponsible of you to say that," he shot back.

Stressing the "unprecedented" nature of the mystery surrounding the airliner's disappearance, Hishammuddin said the authorities would not be bullied into behaving irresponsibly.

If the government disseminates information before it has been properly verified "the people who are going to suffer the most are these very families that we are trying to protect," he said.