WASHINGTON -- How does a Boeing 777 traveling at 35,000 feet disappear from radar with no trace?
"Clearly this is a still a mystery," said CIA director John Brennan during an appearance at the Council on Foreign Relations in Washington Tuesday.
When asked if he would rule out terrorism as a cause in the disappearance of Malaysia Air flight MH370, he responded: "No not all."
Brennan's comments contrasted starkly with Interpol Secretary General Ron Noble's statement earlier indicating the agency was leaning away from terrorism.
But constantly changing and often contradictory developments in the search reignited concerns about terrorism and other possibilities that could have led to the plane's disappearance on Saturday, March 8.
For six days, authorities in Malaysia have struggled to give the world some idea of where the plane is.
Searchers, looking in the waters east of Malaysia, shifted their focus to the nation's western vista after Malaysian authorities revealed the plane may have been tracked near a small island in the Strait of Malacca.
Previously, authorities said the plane disappeared from radar after leaving Kuala Lumpur. Then, a day after authorities announced they were looking for the plane on the western side of Malaysia, a military official reversed course and disputed they were actually looking for it.
Now, instead of the initial search area of more than 12,000 miles, the search area may have doubled.
Military assets from 11 countries, including the U.S., are probing the air and water from the South China Sea, north and east of Kuala Lumpur (where the plane took off from) to the Indian Ocean, south and west of Malaysia.
White House Spokesman Jay Carney told reporters Thursday, "It is my understanding that one possible piece of information has led to the possibility that a new search area may be open in the Indian Ocean."
U.S. Navy 7th Fleet assets were expected to be used in that area.
Pentagon Spokesman Steve Warren told reports midday Monday, "we are continuing to assist the Malaysian government in search and rescue operation in conjunction with the disappearance of flight MH370."
"There are two Arleigh Burke Class Destroyers, the USS Pinckney and the USS Kidd on station in the gulf of Thailand," Warren said.
The Pinckney, according to Warren, "investigated a possible debris field on Sunday, but it was determined not to be associated with flight 370. It was an old shipping crate and a light bulb."
There are two MH-60 Romeo Seahawk helicopters with nighttime search capabilities and FLIR (Forward Looking Infrared) cameras involved. There's also a P-3 Orion surveillance aircraft deployed in the search, with long range search, radar and communications capabilities to the investigation. The USS John Ericsson, a replenishment oiler is also in the area.
Hong Kong aviation authorities reported on Monday that an inbound airliner reported seeing a large field of debris 80 nautical miles southeast of Ho Chi Minh City, which was about 281 nautical miles northeast of the last known radar position.
Ships have been dispatched to the reported debris field.
One of the most prevalent working theories is a catastrophic event in the cockpit of the plane. Aviation experts tell WTOP that the absence of distress signals from the plane suggests the pilots had no time to activate them, could not activate them or chose not to.
Considering the Boeing 777's strong safety record, investigators are looking seriously at the possibility of a terrorism link or hijacking, but have not ruled out the possibility of cabin depressurization, which could cause the crew and passengers to lose consciousness.
The FBI tells WTOP, "We are still closely monitoring the situation and are staying in touch with Malaysian authorities. We stand ready to assist them in their investigation."
Among the growing suspicions is that someone on board the plane caused it to crash.
Authorities in Malaysia have spent several days investigating the crew of the plane. Although authorities have revealed no evidence of a plot at this point, former State Department Counterterrorism Investigator Fred Burton was reminded of the "Bojinka" plot.
"That was a plot by Ramzi Yousef, the mastermind of the first World Trade Center bomber and his efforts to detonate improvised explosive devices in the form of baby doll bombs," Burton said.
Burton said the original plot was designed to attack a dozen or more airlines, "across the south pacific and Asia on flights traveling throughout Asia and inbound to the United States."
The terrorism concern was heightened initially by the discovery that at least two men were traveling on the plane with stolen passports. But Malaysian authorities and Interpol say the men were most likely trying to illegally emigrate to another country.
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