The area of land and sea being covered in the search for Malaysia Airlines flight MH370 measures more than 2.24 million square nautical miles – an area the size of Australia.

In Beijing, meanwhile, distressed relatives of those on board the missing plane have been threatening to go on hunger strike in protest at Malaysia’s handling of the situation.

The relatives say they want clearer information. The Malaysian authorities have said from the start, however, that they will only release information that has been verified and will not respond to the raging speculation about what may have happened to the plane.

Theories range from the quite believable to the far reaches of unimaginable.

Malaysia’s acting transport minister, Hishammudin Hussein, said today that the search for the plane had entered a new phase, which brought new diplomatic, technical and logistical challenges.

Search “more important than politics”

Both Mr Hishammudin and Malaysia’s foreign minister, Seri Anifah Aman, said today that the search operation was more important than politics. Mr Hishammudin urged Malaysians to put their differences aside and unite during this difficult time.

He said the issue of politics had been raised by the foreign media, including Britain’s Daily Mail and the American TV channel CNN.

The Daily Mail called the plane’s captain, Zaharie Ahmad Shah, a political fanatic and said he had attended opposition leader Anwar Ibrahim’s court hearing just before the flight.

Mr Hishammudin said speculation linking the plane’s disappearance to Anwar’s sentencing to five years in jail for sodomy had come from foreign media, not his government.

The foreign minister also said politics was not important and no-one should be seeking publicity on the back of such a major catastrophe.

Friends of Captain Zaharie have rushed to his defence, saying they do not believe he could have hijacked flight MH370. There is no actual evidence that Zaharie or his co-pilot, First Officer Fariq Abdul Hamid, are responsible for the disappearance of the aircraft, but it is thought that someone experienced in aviation must have disabled the plane’s Aircraft Communications Addressing and Reporting System (ACARS) and the transponder.

The authorities say they have not changed their belief that, up until military radar lost contact with the plane at 2.15 a.m. on March 8, its movements, which involved a turnaround from its charted course to Beijing, were consistent with deliberate action.

There is some uncertainty about the exact time that the ACARS was disabled, but the authorities say this has no bearing on the search and rescue operation. They believe the switch-off was between 1.07 and 1.37 a.m.

Most important, they say, is that they know the last position of the plane was either in the northern or southern corridor now being searched. This is thanks to pings to a satellite over the Indian Ocean.

 Search covers 2.24 million square nautical miles

The search for the plane covers a tenth of the world’s surface. It is now focused on two air corridors: a northern one stretching from central Asia to northern Thailand and the other from Indonesia to the southern Indian Ocean.

Mr Hishammudin said each corridor had been divided into seven quadrants, each measuring 160,000 square nautical miles.

Korea, Japan, and the United Arab Emirates are now involved in the search, and are ready to deploy Orions, a Hercules, and other aircraft.

A total of 25 countries are now assisting. Malaysia has asked all Association of Southeast Asian Nations (ASEAN) countries for further support including “assets with deep ocean surveillance detection capabilities”.

Mr Hishammudin said the Royal Malaysian Navy had deployed two more ships to the southern corridor. “This deployment includes a Super Lynx helicopter, which can operate from either ship. This brings the total number of Malaysian ships deployed to the southern corridor to four; with two Super Lynx helicopters.”

Today, Malaysia also deployed two C-130 aircraft to the Indonesian sector of the southern search corridor, Mr Hishammudin said.

The United States has deployed one P-8 Poseidon military planes, and will redeploy a P-3 Orion aircraft. Australia has deployed three P-3 Orions and one C-130 Hercules.

Malaysia is asking other countries, and especially the US, for satellite and radar data that may help refine the search.

The Indonesian military have been asked to look again at any satellite or other data they have that might be of help.

There were many more challenges in the southern corridor than the north, Mr Hishammudin said, because the area was so huge.

Australia and Indonesia are leading the search in the southern corridor.

Possible technical fault not yet ruled out

There has been little focus on the idea that the plane may have had a technical fault, but Malaysia’s director-general of civil aviation, Azharuddin Abdul Rahman, said today that no possibility was being discounted.

While the theory of malfunction is still being discussed, the CEO of Malaysia Airlines, Ahmad Jauhari Yahya, said satellite communication was still active until 8.12 a.m., so there was still some functionality in the system even though the ACARS and the transponder had been disabled.

Asked whether the plane might have been programmed to follow an unscheduled route, Mr Ahmad said that, as far as the airline was concerned, the aircraft was programmed to fly to Beijing.  However, he did add that “once you are in the aircraft anything is possible”.

Malaysia is also asking other countries to look again at their military radar data. The authorities here say they cannot give information about other countries’ military radar. The only country that had revealed this primary radar information was Malaysia, Mr Hishammudin said.

He said again that finding the aircraft and those on board was more important than national security.