BEIJING — Frustration mounted on Monday over what has become one of the most perplexing aviation disasters in history, as the search for a vanished Malaysia Airlines passenger jet entered a third day and dramatically expanded its area of operations.
Hopes for a breakthrough were dashed when Malaysian authorities said oil found on the ocean surface had been tested and found not to have come from the jet liner, while various pieces of flotsam picked up in the vicinity of the plane’s last known location were also found to be unconnected.

“This unprecedented missing aircraft mystery -- as you can put it -- it is mystifying,” Azharuddin Abdul Rahman, director-general of Malaysia’s Department of Civil Aviation said at a news conference in Kuala Lumpur.
“To confirm what happened that day on this ill-fated aircraft, we need hard evidence. We need concrete evidence. We need parts of the aircraft for us to analyze, for us to do forensic studies,” he said. “We are every hour, every minute, every second, looking at every inch of the sea.”
About 40 ships and 34 aircraft from nine countries are combing a vast area of ocean in the Gulf of Thailand and the South China Sea, northeast of Malaysia towards Vietnam. The search expanded Sunday into areas well beyond the plane’s intended northeasterly flight path towards China. Authorities are now looking even at areas in the Adaman Sea, on the western side of the Malaysian peninsula.
For the plane to have crashed into the Andaman Sea would imply that it had somehow turned back and crossed the entire Malaysian peninsula without being detected by radar operators.
Malaysian authorities said Sunday that the plane may have turned around before disappearing from radar without a distress call. If true, aviation experts said this could offer a clue as to why no debris had yet been found.
“Was this turn under pilot command, hijacker command, or induced by a structural failure of some kind -- either by an airplane fault or by a bomb?” wrote Scott Hamilton, an aviation expert and founder of Leeham News and Comment, in an email from Seattle.
“If the airplane deviated from its planned flight path (as a turn might indicate), they are looking in the wrong place. Also, the fact that no debris whatsoever has emerged from where they are looking, this certainly suggests to me they are looking in the wrong place, whatever the reason.”
The USS Pinckney, a destroyer in the U.S. Navy’s 7th Fleet, has joined the search.
In a phone interview on Monday Navy Commander William Marks from the 7th Fleet told the BBC that the destroyer and its onboard aircraft have infrared, sonar and other search capabilities, and can also listen for any signal emitted from the plane’s black box.
“Just from the air we can see things as small as almost the size of your hand or a basketball. It’s not a matter of if we can see it. It’s an extremely large area,” he said. As more time passes, currents and wind as well as the expanding size of the search area are making the task more difficult.
On Monday, hopes briefly centered on a rectangular orange object that authorities said might have been a lifejacket. But when a Vietnamese helicopter recovered the piece of flotsam, it was identified as “a moss-covered cap of a cable reel,” the Civil Aviation Authority of Vietnam said on its website.
This was not the first time hopes have been dashed in the past two days.
Late on Sunday afternoon, Vietnamese authorities said one of their aircraft had spotted a rectangular object that could have been an inner door from the missing plane, but it was too dark to be sure. By Monday, ships and planes had returned to the area, but could not locate the object. Meanwhile, sightings of what had resembled a piece of the plane’s tail turned out to be logs tied together to form a pontoon, Malaysian authorities said.
Two oil slicks, between six and nine miles long, consistent with fuel left by a downed jetliner, were located on Saturday in the region where the plane vanished. But on Monday tests concluded they were not connected to the plane.
Speculation that terrorists could have brought down the plane had been fueled by reports that two men boarded using stolen passports, but experts said this could easily have been a coincidence.
On Monday, Azharuddin said closed circuit television footage had shown the men had passed through normal security checks at the airport, and were not of Asian appearance. Officials also said they had shared “biometric and visual” information about the men with U.S. intelligence agents.
“We looked at the video and the photograph,” Azharuddin said. “It is confirmed now that they are not Asian-looking men.”
When asked for more detail about the men, Azharuddin said: “Do you know of a footballer by the name of Balotelli? He’s an Italian. Well you know how he looks like?”
Mario Balotelli is an Italian professional soccer player whose parents were immigrants from Ghana.
Luigi Maraldi, 37, of Italy and Christian Kozel, 30, of Austria had initially been listed among the plane’s passengers, but both were subsequently found to be safe — and to have had their passports stolen.
Booking information accessed through the KLM Web site showed that the passengers using the passports had adjacent ticket numbers and that both were booked on a subsequent flight from Beijing to Amsterdam. One, traveling under Maraldi’s name, was to continue to Copenhagen and the other to Frankfurt, Germany. Their itineraries were separately confirmed by an employee of China Southern Airlines, which was a code-share partner on the flights and sold them the tickets.
Nevertheless, Interpol statistics show that 39 million passports were lost or stolen as of the end of last year, and experts said travelers in Asia often use stolen documents. The international police agency expressed frustration Sunday that few of its 190 member countries “systematically” searched the database to determine whether documents being used to board a plane are listed as lost or stolen.
Azharuddin said investigators were now looking at whether the two men were linked to a “stolen passports syndicate.”
Earlier, he said five other passengers had checked in for the flight but never boarded, and insisted their baggage had been removed before the plane took off.
Of the 239 people on board, 154 were from China or Taiwan, and relatives of many of them have been gathered at a hotel in Beijing for the past two and a half days, growing increasingly frustrated at the lack of news.
For the second day in a row, families threw water bottles Monday at officials from Malaysia Airlines sent to brief them. More than 100 signed a petition demanding greater efforts from the airline and their own government, whom they accused of avoiding them.
“Why are you here so late?” “Do you know what day it is?” relatives shouted at Chinese government officials Monday. “All you said is just empty talk,” said one woman.
“Why have you just showed up now?” said another woman. “The window time for rescue has passed. My tears have already dried up.”
Chinese officials insisted they were doing the best they could, but at the same time they have expressed increasing impatience with Malaysia’s handling of the investigation.
China has sent two ships to help in the search as well as dispatching foreign ministry, public security and civil aviation officials to Malaysia. More ships were on their way, officials said, while foreign ministry spokesman Qin Gang urged Malaysia to “step up their efforts and speed up their investigation” and to make sure China and Chinese passengers’ families “find out the truth of things as soon as possible.”
In the absence of physical evidence about what happened to Flight MH370, sketchy claims emerged of a possible link to Muslim extremists from China’s Uighur ethnic minority, but were downplayed by the authorities.
In Taiwan, the head of national intelligence said a telephone call had been received on March 4 suggesting that an extremist Muslim group from China’s ethnic Uighur minority would mount a terrorist attack on Beijing International Airport – but added he did not believe the call was linked to the vanished airliner.
Police told local media the caller had rung from the southern Chinese city of Guangdong. He had spoken first in French, claiming to be an anti-terrorism official from that country, and then switched to Chinese with a southern accent. But Tsai De-sheng, the head of Taiwan’s National Security Bureau, said he did not believe the warning was “highly correlated” with the vanished airliner, according to state media.
Similarly, a Chinese Internet activist and journalist based in New York said he had received an email claiming the plane had been attacked to protest Chinese “oppression and persecution” of its Uighur minority, as well as persecution by the Malaysian government, which has repatriated Uighur refugees to China in the past.
The Chinese government warned the public against jumping to conclusions and circulating rumors.
“The investigation of this incident is still underway, and it is still too early to jump to conclusions at this stage,” Foreign Ministry spokesman Qin Gang told a news conference. “We also hope general public will stay calm and adopt a responsible attitude.”
Earlier this month, knife-wielding assailants killed 29 people at a railway station in the southwestern Chinese city of Kunming, in one of the worst terrorist attacks in the country’s history. The Chinese government said the perpetrators were separatist Uighurs from the western province of Xinjiang.
Nevertheless, to move from knife attacks to international terrorism and downing airliners would be a massive leap for Uighur extremists, who are not thought to have strong links to the global jihadist movement.
On Sunday, a senior U.S. counterterrorism official said there were no indications of terrorism, although nothing had been ruled out.
Asked about the possibility of a terrorist attack, Azharuddin said: “There is talk of possible hijack. And this is not discounted by us. We are looking at every angle, we are looking at every aspect of what could have happened on this ill-fated aircraft on the morning of Saturday.”
Asked if hijackers might have been able to force their way into the cockpit and take control of the plane, Malaysia Airlines chief executive Ahmad Jauhari Yahya said that according to international protocol following the 9/11 attacks, the plane’s cabin door would have been locked from the inside, and a video camera installed to show who was outside the door.
The flight lost contact with Malaysian air traffic control at 1:20 a.m. Saturday, less than an hour after taking off from Kuala Lumpur, after completing its ascent. It vanished on the border of the territorial waters of Malaysia and Vietnam, where the Gulf of Thailand meets the South China Sea.
It had been due to land in Beijing at 6:30 a.m. Saturday.
Azharuddin said investigators from the U.S. Federal Aviation Administration and National Transportation Safety Board had arrived in Malaysia to assist in the investigation.
Harlan reported from Seoul. Liu Liu, Gu Jinglu and Xu Jing in Beijing contributed to this report.
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