Malaysia's transport minister ordered an inquiry after security guards carried out the distraught mother of a passenger on Malaysia Airlines Flight MH370 from a briefing room where she had protested about a lack of transparency, 12 days after the plane vanished.
"They are just saying wait for information. Wait for information. We don't know how long we have to wait," cried the woman before being whisked away from a massive media scrum.
Minister Hishammuddin Hussein said he regretted the anguish.
"Malaysia is doing everything in its power to find MH370 and hopefully bring some degree of closure for those whose family members are missing," he said in a statement.
Prospects that a 26-nation operation would lead to quick results appeared to be dwindling, however, as investigators confirmed they were focusing on the remote southern Indian Ocean after failing to find any traces of the jet further north.
"Our top priority is being given to that area," Hishammuddin told the news conference, confirming an earlier Reuters report.
No wreckage has been found from Flight MH370, which vanished from air traffic control screens off Malaysia's east coast at 1.21am local time on March 8 (1721 GMT March 7), less than an hour after taking off from Kuala Lumpur bound for Beijing.
An unprecedented search for the Boeing 777-200ER is under way in two vast search corridors: one arcing north overland from Laos towards the Caspian Sea, the other curving south across the Indian Ocean from west of Indonesia's Sumatra island to west of Australia.
Meanwhile, investigators are trying to restore files deleted last month from the home flight simulator of the pilot aboard the missing Malaysian plane to see if they shed any light on the disappearance, Malaysia's acting transport minister said on Wednesday.
Hishammuddin Hussein told a news conference that the pilot, Captain Zaharie Ahmad Shah, is considered innocent until proven guilty of any wrongdoing, and that members of his family are cooperating in the investigation. Files containing records of simulations carried out on the programme were deleted on February 3, Malaysian police chief Khalid Abu said.
Deleting files would not necessarily represent anything unusual, especially if it were to free up memory space, but investigators would want to check the files for any signs of unusual flight paths that could help explain where the missing plane went.
The military in the Maldives, a remote Indian Ocean island nation, confirmed to Malaysia that reports of a sighting of the plane by villagers there were "not true," the Malaysian minister said.
Investigators probing the disappearance of the jetliner believe it most likely flew into the southern Indian Ocean, a source close to the investigation said on Wednesday.
"The working assumption is that it went south, and furthermore that it went to the southern end of that corridor," said the source, who spoke on condition of anonymity.
The view is based on the lack of any evidence from countries along the northern corridor that the plane entered their airspace, and the failure to find any trace of wreckage in searches in the upper part of the southern corridor.
Some sources involved in the investigation have voiced fears it could be drifting towards deadlock due to the reluctance of countries in the region to share militarily sensitive radar data or allow full access to their territory.
"These are basically spy planes, that's what they were designed for," said one source close to the investigation, explaining the hesitance of some nations to allow maritime surveillance aircraft into their waters.
Last week, a source familiar with official US assessments said it was thought most likely the plane flew south, where it presumably would have run out of fuel and crashed into the sea.
If it did indeed end up in the southern Indian Ocean, one of the remotest places on Earth and also one of the deepest seas, it increases the chance it may never be found – and investigators may never know for sure what happened on board.
Hishammuddin said the difficulty of searching such a huge expanse of ocean made the operation in the southern corridor "much more challenging".
Officials believe that someone with detailed knowledge of both the Boeing 777 and commercial aviation navigation switched off two vital datalinks: the ACARS system, which relays maintenance data back to the ground, and the transponder, which enables the plane to be seen by civilian radar.
Malaysia Airlines Flight 370 with 239 people aboard disappeared March 8 on a night flight from Kuala Lumpur to Beijing. Malaysian authorities have not ruled out any possible explanations, but have said the evidence so far suggests the flight was deliberately turned back across Malaysia to the Strait of Malacca, with its communications systems disabled. They are unsure what happened next and why.
Read: Files were deleted from flight simulator, says Malaysia
Read: Reports of MH370 sighting over Maldives untrue: Malaysia minister
Investigators have identified two giant arcs of territory spanning the possible positions of the plane about seven-and-a-half hours after takeoff, based on its last faint signal to a satellite — an hourly "handshake" signal that continues even when communications are switched off. The arcs stretch up as far as Kazakhstan in central Asia and down deep into the southern Indian Ocean.
Police are considering the possibility of hijacking, sabotage, terrorism or issues related to the mental health of the pilots or anyone else on board, and have asked for background checks from abroad on all foreign passengers.
Hishammuddin said such checks have been received for all the foreigners except those from Ukraine and Russia - which account for three passengers. "So far, no information of significance on any passengers has been found," Hishammuddin said.
The 53-year-old pilot joined Malaysia Airlines in 1981 and had more than 18,000 hours of flight experience. People who knew Zaharie from his involvement in opposition political circles in Malaysia and other areas of his life have described him as sociable, humble, caring and dedicated to his job.
The crisis has exposed the lack of a failsafe way of tracking modern passenger planes on which data transmission systems and transponders — which make them visible to civilian radar — have been severed. At enormous cost, 26 countries are helping Malaysia look for the plane.
Read: Nothing suspicious found in flight simulator of MH370 pilot
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Relatives of passengers on the missing airliner — two thirds of them from China — have grown increasingly frustrated over the lack of progress in the search. Planes sweeping across vast expanses of the Indian Ocean and satellites peering on Central Asia have turned up no new clues.
"It's really too much. I don't know why it is taking so long for so many people to find the plane. It's 12 days," Subaramaniam Gurusamy, 60, said in an interview from his home on the outskirts of Kuala Lumpur. His 34-year-old son, Pushpanathan Subramaniam, was on the flight heading to Beijing for a work trip.
An unidentified woman with her face painted, depicting the flight of the missing Malaysia Airline poses in front of the "wall of hope" at Kuala Lumpur International Airport in Sepang. (AP photo)
"He's the one son I have," Subaramaniam said.
Before Wednesday's news briefing at a hotel near the Kuala Lumpur airport, two Chinese relatives of passengers held up a banner saying "Truth" in Chinese and started shouting before security personnel escorted them out.
"I want you to help me to find my son!" one of the two women said.
Hishamuddin announced that a delegation of Malaysian government officials, diplomats, air force and civil aviation officials will head to Beijing — where many of the passengers' relatives are gathered — to give briefings to the next of kin on the status of the search.
Aircraft from Australia, the US and New Zealand on Wednesday scoured a search area stretching across 305,000 square km of the Indian Ocean, about 2,600 km southwest of Perth, on Australia's west coast. Merchant ships were also asked to look for any trace of the plane.
Nothing has been found, the Australian Maritime Safety Authority said.
Read: Why do airplane transponders have an 'off switch'?
China has said it was reviewing radar data and deployed 21 satellites to search the northern corridor, although it is considered less likely that the plane could have taken that route without being detected by military radar systems of the countries in that region.
Those searches so far have turned up no trace of the plane, Chinese Foreign Ministry spokesman Hong Lei said.
A map of a flight plan is seen on a computer screen during a meeting before a mission to find the Malaysia Airlines flight MH370 that disappeared from radar screens. (Reuters photo)
Indonesian defence minister Purnomo Yusgiantoro said Indonesia military radar didn't pick up any signs of Flight 370 on the day the plane went missing. He said Malaysia had asked Indonesia to intensify the search in its assigned zone in the Indian Ocean west of Sumatra, but said his air force was strained in the task.
"We will do our utmost. We will do our best. But you do have to understand our limitations," Purnomo said.
Hishammuddin said both the southern and the northern sections of the search area were important, but that "some priority was being given to that (southern) area." He didn't elaborate.
Read: Missing plane bolsters racial unity in Malaysia
Malaysian investigators say the plane departed 12.41am on March 8 and headed northeast toward Beijing over the Gulf of Thailand, but that it turned back after the final words were heard from the cockpit. Malaysian military radar data places the plane west of Malaysia in the Strait of Malacca at 2.14am.
Thailand divulged new radar data on Tuesday that appeared to corroborate Malaysian data showing the plane crossing back across Peninsular Malaysia.
German insurance company Allianz said on Wednesday that it has made initial payments in connection with the missing plane. Spokesman Hugo Kidston declined to say how much had been paid, but said it was in line with contractual obligations when an aircraft is reported as missing.
Read: US rules out MH370 landed at its Indian Ocean base in Diego Garcia
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