Uncertainty continues to surround the disappearance of Malaysia Airlines flight 370 on March 8. The search area for the plane, which was heading from Kuala Lumpur to Beijing, carrying 239 passengers and crew, has vastly expanded.

Search efforts initially focused on the South China Sea, but the Malaysian military announced last week that it had tracked the jetliner veering off course and back across the Malaysian peninsula into the Strait of Malacca. Information from British satellite communications provider Inmarsat indicates that the plane continued to fly for seven hours after its Aircraft Communication Addressing and Reporting System (ACARS), the transponder used by civilian air traffic controllers to track aircraft, stopped functioning.

The current search zone covers 2.4 million square nautical miles stretching from Central Asia to the Indian Ocean—an area almost the size of the Australian continent. Commander William Marks, a spokesman for the US 7th Fleet, told the Associated Press that finding the plane was like trying to locate a few people somewhere between New York and California.

The families of the missing passengers are increasingly angry and distraught at the endless delays and the uncoordinated search effort. Passenger Pushpanathan Subramaniam’s father told the Associated Press: “I don’t know why it is taking so long for so many people to find the plane. It’s 12 days.” Several Chinese family members protested at a media conference and threatened to go on hunger strike, accusing the Malaysian government of withholding information about the flight.

Searchers now say they believe the plane probably flew south. A New York Times report on Tuesday quoted “current and former military officers” who said the plane was unlikely to have flown over the Asian mainland without being detected. The Chinese, Indian and Pakistani borders are all heavily militarised, and US occupying forces in Afghanistan have their own radar installations. An Indian air force official said there was “no way or the slightest possibility of our radars having missed the plane.”

Although 26 countries are currently involved in the search, efforts to pinpoint the plane are being hampered by an unwillingness to share any information gathered by their military and intelligence agencies.

Ian Storey, a senior fellow at Singapore’s Institute of Southeast Asian Studies, told Reuters: “Information and intelligence exchange is very sensitive in this part of the world, where there is a lot of distrust and sovereign issues. Countries are unwilling to share sensitive intelligence because it reveals their military capabilities—or lack of capabilities.”

The area surrounding the Malacca Strait has become one of the most strategically crucial in the world, particularly because the Obama administration’s “pivot” to Asia to counter China includes a heavy focus on control over China’s maritime trade routes, many of which pass through the region.

On Tuesday, Thailand’s military revealed that it had tracked the plane flying west over the Malaysian peninsula, corroborating the Malaysian intelligence. Thai authorities gave no explanation for why they waited 10 days to release the information, merely saying they had not been asked for it.

The Wall Street Journal reported that Indian officials “gave conflicting comments Monday about whether radar systems on the Andaman and Nicobar Islands were operational” on March 8, when flight MH370 may have crossed the area.

Malaysian Defence Minister Hishamuddin Hussein, who is the country’s acting transport minister and leading its search effort, declared on Tuesday: “The only [country] that is basically out in the open is Malaysia.” He told reporters that Malaysia had “put aside national security” and urged other countries to “decide what sort of military and other data they are willing to share with us.”

According to Reuters, “Malaysia says it will have to buy a new radar system after revealing what it knew of the path the airliner took after turning back across its territory.”

US President Barack Obama made his first public comments on the missing plane on Wednesday, 11 days after it vanished. He told Fox News: “We have put every resource that we have available at the disposal of the search process.” He claimed to be working in “close cooperation with the Malaysian government.” The US pressured Malaysia to let FBI investigators into the country, where they are reportedly assisting by investigating the backgrounds of the pilots and crew.

Contrary to Obama’s claims, the Malaysian defence minister told the New Straits Times yesterday that he had appealed to the US to share information from its top secret surveillance base in central Australia—Pine Gap, near Alice Springs. Hishammuddin said the US had “possibly the best ability” to locate the plane using its satellite and radar systems.

Pine Gap’s operations are extremely sensitive. It is used to locate phone and radio signals from the Middle East right across Asia to China, North Korea and the Russian Far East. It also gathers Internet data as part of the US National Security Agency’s mass surveillance programs.

The base plays an integral part in the Obama administration’s selection of targets for drone assassination in Afghanistan and Pakistan, as well as Washington’s preparations for a war with China. Last July, an Australian intelligence source told Fairfax Media: “The US will never fight another war in the eastern hemisphere without the direct involvement of Pine Gap.” (See: “Australian spy base “critical” to Obama’s drone assassinations”)

The New Straits Times also reported that the Australian Defence Department refused to supply information from its Jindalee Operational Radar Network (JORN) in Western Australia. Fairfax Media cited unnamed experts who said JORN’s powerful “over-the-horizon” radar “can detect movements across 37,000 square kilometres.”

For public relations purposes, Australian Prime Minister Tony Abbott announced that Australia is leading the search for MH370 in a 600,000 square kilometre area of the southern Indian Ocean. An Australian Maritime Safety Authority official said this was like looking for a “needle in a haystack.”

It remains unclear whether the plane was hijacked, and if so, by whom. China’s ambassador to Malaysia Huang Huikang said on Tuesday there was no evidence that any of the Chinese nationals on the plane, who were the majority of its passengers, were responsible for its disappearance.

Malaysia Airlines chief executive Ahmad Jauhari Yahya told the media yesterday that a technical malfunction aboard the plane was unlikely because the satellite communication system remained active for seven hours after the civilian transponder was “disabled.” According to US and Malaysian investigators, the plane’s altered flight path had to be programmed into its computer navigation system by someone familiar with the technology.

Investigations of the pilots, passengers and crew, however, have reportedly found nothing to suggest that any of them were part of a hijacking or terrorist plot.