U.S. counterterrorism specialists are taking seriously a threat Tuesday by Pakistani Taliban leader Baitullah Mehsud to attack the White House and "amaze" the world.
Mehsud, who has a $5 million bounty on his head and has taken responsibility for a string of terrorist attacks in Pakistan - including a bold assault on a police training center in Lahore on Monday that killed more than 30 people - has made similar threats before.
In recent years, however, Mehsud has gained strength and territory. In February, he united with two other Pakistani Taliban groups and pledged allegiance to Afghan Taliban leader Mullah Mohammed Omar. The U.S. has tried repeatedly to kill Mehsud with drone attacks.
Mehsud, in phone calls to foreign and local news agencies on Tuesday, said his attacks against the Pakistani government were in response to the drone strikes on Pakistan's lawless borderlands, where Mehsud is thought to be hiding.
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"Soon we will launch an attack in Washington that will amaze everyone in the world," Mehsud said, according to the Associated Press. He provided no details.
FBI spokesman Richard Kolko said the FBI was aware of the claims but had no information about "any imminent or specific threats to the U.S."
However, a bulletin has been issued to law enforcement authorities nationwide to be vigilant for attacks connected with Mehsud, said U.S. officials who asked not to be named because of the sensitive nature of their work.
Frances Fragos Townsend, counterterrorism and homeland security adviser to President Bush from 2003 to 2008, said Mehsud threatened last year "to burn down the White House and nothing happened. The only way he can do something is if he leverages al Qaeda's capability around the world and specifically in the United States. The extent of any al Qaeda operational capability here is an open question for the federal government. That said, this is a guy who has killed Americans. This is a tribal chief who has American blood on his hands, and that alone is why we take him seriously."
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Mary Habeck, a professor of strategic studies at Johns Hopkins University´s School of Advanced International Studies and the author of "Knowing the Enemy," added, "I always take these guys seriously. The Pakistani Taliban has evolved over the past three years from a multitude of different groups with a variety of motivations into a much more homogenous movement that is concerned not just with repelling incursions into Waziristan [a tribal area on the Afghan-Pakistan border] by the Pakistani military, but with spreading their beliefs and ideology throughout northern Pakistan. I believe Baitullah Mehsud has sworn an oath of allegiance to Mullah Omar, and so has al Qaeda."
For the past several months, U.S. pilotless aircraft have been targeting the Taliban leader in part in hopes of pre-empting a spring offensive by the extremists against U.S.-led forces in Afghanistan.
In 2007 and 2008, the U.S. military avoided hitting Mehsud's forces, despite the Taliban leader's continuous campaign of suicide bombings inside Pakistan, including the assassination of former Prime Minister Benazir Bhutto.
Mehsud's alliance in February, however, with other Taliban commanders in North and South Waziristan gave him an inlet into Afghan territory.
He also has developed close ties to al Qaeda, U.S. counterterrorism officials said.
A U.S. defense official with knowledge of operations in the region said Mehsud poses a significant threat to U.S. troops as "his terrorist network has grown in size and he has much more capabilities than he did in the past."
The official spoke on the condition of anonymity because of the nature of his work.
The official said Mehsud's latest threat might be "more of a propaganda campaign" because Mehsud is "feeling the pressure on him, the bull's-eye on his back. But you can never underestimate what these guys are capable of."