WASHINGTON: With malicious intent strongly suspected in the disappearance of Malaysia Airlines Flight 370, US intelligence and law enforcement agencies renewed their search over the weekend for any evidence that the plane's diversion was part of a terrorist plot. But they have found nothing so far, senior officials said, and their efforts have been limited by the Malaysian authorities' refusal to accept large-scale US assistance.
There are just two FBI agents in Kuala Lumpur, the Malaysian capital, where local investigators are hunting for clues that the two pilots or any of the other 237 people on board had links to militant groups or other motives to hijack the flight.
In the days after the plane went missing on March 8, US investigators scoured their huge intelligence databases for information about those on board but came up dry.
"We just don't have the right to just take over the investigation," said a senior US official who, like others, spoke on the condition of anonymity because the investigation was continuing. "There's not a whole lot we can do absent of a request from them for more help or a development that relates to information we may have."
With no obvious motive apparent, US investigators are considering a range of possibilities, though they caution that all remain merely speculative. Among them are involvement by al-Qaida's Southeast Asian affiliate, which once discussed recruiting commercial pilots in Malaysia to crash a plane; an act by members of China's Uighur minority, who have recently become more militant and could conceivably have targeted a plane headed to Beijing; a lone-wolf attack by someone without ties to established terrorist groups; or even a suicidal move by a troubled individual.
A central puzzle is why anyone would hijack a jetliner and then fly it for hours over the open ocean, as seems to be the most likely case. On Saturday, the Malaysian authorities opened a criminal inquiry after learning that two tracking devices aboard the aircraft had been turned off several minutes apart, indicating deliberate action, and that the plane appeared to have flown for as long as seven hours more.
US officials said the announcement of the criminal investigation did not change their view of the situation, as the Malaysians offered little evidence that had not already been learned in the past week.
Several senior US officials have played down the possibility that a terrorist network was behind the plane's disappearance because no group has claimed responsibility for it. They said intelligence agencies had not detected chatter among terrorists about such a plot. Given the lack of traditional militant "signatures," one official said, if terrorists were behind the episode, "it would be unlike anything we have seen before."
In response to the news that Malaysian authorities had taken a flight simulator from the chief pilot's home, US officials said that they were eager to know what the investigators had found and were willing to help search the computers. But as of Sunday afternoon, the officials said they knew little about the findings.
As part of their efforts in the days after the plane went missing to determine what had occurred, US analysts and law enforcement agencies conducted link analysis — a computer-based investigative technique that tries to make connections between individuals based on extensive government and airline databases - on the pilots and two Iranian passengers who were traveling on stolen passports. Those efforts, along with interviews with family members of the Iranian men and of two Americans who were on the plane, yielded nothing that pointed to terrorism, officials said.
"If it is a criminal act where the pilot decided to crash the airliner, there is little the US can do," said Rick Nelson, vice president of business development at Cross Match Technologies and a former senior counterterrorism official. "It's very difficult to stop someone who one day decides to crash a plane. It is difficult to predict and to mitigate."
The FBI, which has had an agent based at the US Embassy in Kuala Lumpur for more than a decade, has developed a working relationship with law enforcement officials there in recent years. But US officials said they believed that the Malaysian leaders had rebuffed their offers of assistance because they did not want to appear as though they needed help with such a high-profile investigation.
Because two-thirds of the passengers were Chinese, one group with a conceivable motive to hijack the plane would be militant members of the Muslim Uighur ethnic group in China. Malaysian and Chinese news reports identified one passenger as Uighur, but US officials said they had no evidence that the passenger was associated with militant groups.
On Friday, Abdullah Mansour, the leader of the rebel Turkestan Islamic Party, told Reuters in an interview from his hide-out in Pakistan that the Uighurs' "fight against China is our Islamic responsibility." But he made no mention of the missing airliner.
Investigators are keeping in mind the long history of al-Qaida connections and terrorist plots in Southeast Asia, including the double bombing of nightclubs in Bali, Indonesia, in 2002, which killed more than 200 people. That attack was carried out by members of Jemaah Islamiyah, a regional militant group with close ties to al-Qaida.
As investigators focus on the pilots and study possible motives for a hijacking, certain tactics that al-Qaida and Jemaah Islamiyah considered years ago may be newly relevant. In 2001, leaders of the two groups discussed recruiting a Malaysian or Indonesian commercial pilot for a terrorist mission, according to a 2006 book by Kenneth J. Conboy, an American author who specializes in militant groups in Southeast Asia.
Khalid Shaikh Mohammed, the chief planner of the Sept. 11 attacks, considered using such pilots for a second wave of attacks on buildings or landmarks in the United States. Yazid Sufaat, a Malaysian who studied biochemistry at California State University and experimented with biological weapons for al-Qaida before Sept. 11, proposed crashing a commercial airliner into a passing US warship, the aircraft carrier Kitty Hawk, according to a local intelligence report cited in Conboy's book on Jemaah Islamiyah, "The Second Front."
Yazid was free from 2008 until last year, when he was detained in Malaysia and charged with helping to recruit fighters to send to Syria. He remains in custody.
