The U.S. Justice Department today charged three men with plotting to attack major financial institutions in New York, New Jersey and the nation's capital.
Dhiran Barot, 32, Nadeem Tarmohammed, 26, and Qaisar Shaffi, 25, are accused of scouting the New York Stock Exchange and Citicorp Building in New York, the Prudential Building in Newark, N.J., and the International Monetary Fund and World Bank in the District of Columbia.
The government believes the men were sent to the United States by Osama bin Laden in 2000 and 2001.
"It highlights the nature of the enemy we face -- an enemy that is patient, that is spread throughout the world and that is bent on killing Americans in a spectacular way," U.S. Deputy Attorney General James Comey told a news conference today.
Barot, a British national of Indian descent who is also known as Eisa al-Hindi, was the alleged leader of the plot. The other two defendants are also British nationals.
The government says Barot and his team meticulously scouted and videotaped the buildings for hours. The surveillance was discovered on the computer disk of an al Qaeda suspect arrested in Pakistan last year.
According to government documents obtained by ABC News, Barot appeared fixated on the destructive power of glass as shrapnel.
The group's reconnaissance points to "the abundance of glass" in some buildings, noting that there were "public atriums, skylights and glass doors."
Documents: Group Sought Maximum Carnage
The documents suggest Barot wanted to kill as many people as possible, taking special note of buildings where there was a lack of escape routes.
The suspects observed when the greatest number of people would be entering, leaving and walking in front of the buildings, according to the documents. They also discussed renting office space and "detonating a device from within," the documents say.
"They knew what to look for. They were experts," said Richard Clarke, a former White House counterterrorism official who is now an ABC News consultant.
"It was a serious effort," said Jack Cloonan, a former FBI agent who interviewed a number of captured al Qaeda members and is now an ABC News consultant. "They're not going to expose three people to being arrested unless they were they were very serious about hitting these targets."
According to today's indictment, Barot was "lead instructor at a jihad training camp in Aghanistan" in 1998. The report by the independent commission that investigated the 9/11 attacks suggests he was one of bin Laden's top lieutenants in Europe.
While in the United States, Barot posed as a student, the FBI says. ABC News has learned he applied for admission at Mohawk Valley Community College in upstate New York, but never enrolled.
Barot and the two other suspects were arrested this summer in Britain. British police say they recovered the group's surveillance reports, video of the U.S. financial buildings and notebooks on explosives and poisons.
Justice Department officials say they plan to extradite the men after they are prosecuted in Britain. Law enforcement officials fear the surveillance team had a support network in the United States.
"Al-Hindi is a major al Qaeda player," New York City Police Commissioner Ray Kelly told reporters today. "And we have to be concerned about other people who he was associated with and so-called franchise operations that may be out there."
Government sources say al Qaeda actively considered the plan to attack U.S. financial institutions until August of last year.
ABC News' Pierre Thomas filed this report for "World News Tonight."