Bulletin Details Al Qaeda Tactics

A new government intelligence bulletin describes in the greatest detail yet Al Qaeda's (search) techniques for assessing potential targets, extolling the lethal power of flying, shattered building glass and advising that kerosene and tires are effective for a deadly arson attack.

"The focus is on maximizing the destructive and killing power of an attack," the bulletin says.

The bulletin provides a fresh glimpse of terrorist reports found in computers and disks seized in Pakistan in July. The reports described the casing by terrorists of several buildings in the United States and prompted U.S. authorities to raise the terror threat level earlier this year for high-profile financial facilities in New York, Washington and Newark, N.J.

The heightened alert was eased shortly after the Nov. 2 election, and there is no evidence a potential attack ever moved beyond initial planning.

"Current intelligence provides no indications that Al Qaeda has operatives to conduct an attack based upon the information in these reports," the eight-page bulletin said.

Produced by the FBI and Homeland Security Department (search), the bulletin was circulated Tuesday to law enforcement, government and industry officials nationwide and obtained Wednesday by The Associated Press.

The excerpts, according to the bulletin, show that Al Qaeda operatives go well beyond basic description of a potential target to sophisticated analysis of vulnerabilities in building construction, an examination of potential police and emergency response and recommendations for possible methods of attack.

In one report, an unidentified Al Qaeda operative notes that a building "is almost completely made to resemble a glass house — which could be devastating in an emergency scenario ... that is to say, that when shattered, each piece of glass becomes a potential flying piece of cutthroat shrapnel!"

Another excerpt calculates that a particular building has precisely 67,000-square-feet of glass, adding for emphasis that it amounts to "an acre and a half of glass."

The author provides five possible methods of attack in one scenario, leading with parking a vehicle packed with explosives next to an exposed building column. The terrorist also suggests that operatives rent space in the building or use any of several substances in an arson attack.

"Combinations with leaking gas cylinders (esp. oxygen), bleach, ammonia and tires (they burn well) could be lethal," the Al Qaeda report says. "Added to this, also be advised that kerosene burns more powerfully than an ordinarily fueled fire (although it may not be hot enough to melt steel unless used in very large quantities)."

The reports note such things as when people take lunch and smoking breaks, where surveillance cameras are positioned, what public events were scheduled near buildings and how many cars and pedestrians typically pass by per minute. Detailed descriptions of security guards included their uniforms, whether they were armed and a notation that one male guard's weapon "appears to be a Colt .45 pistol."

In two reports, the Al Qaeda author assumed that undercover security officers are likely to be stationed near possible targets. That shows that security officials must "regularly review, refresh and reinforce" their undercover teams to prevent them from being identified, the bulletin said.

One Al Qaeda operative also advises where additional reconnaissance could be performed before an attack, such as "inside the coffee shop, restaurants or bars etc. Or even on the upstairs floor of the bookshop (there is one end where people regularly sit and browse through books)."

The bulletin said the casing reports demonstrate a high level of sophistication among Al Qaeda surveillance operatives and suggest that the terror group wants to use people who have experience living in the United States to help choose targets.

Many of the reconnaissance techniques are described in a captured Al Qaeda manual titled "Military Studies in the Jihad Against the Tyrants (search)." That manual says that public information can provide 80 percent of the information needed about a possible target, demonstrating that security officials in government and the private sector must carefully review what is available on the Internet and elsewhere, the bulletin said.

"Surveillance of a potential target can occur as little as one week to as much as three years prior to an attack," the bulletin said.