Senior law enforcement officials have told the New York Times that the FBI is tracking hundreds of muslims in its search for terrorist plots within the U.S.

"The surveillance campaign is being carried out by every major F.B.I. office in the country and involves 24-hour monitoring of the suspects' telephone calls, e-mail messages and Internet use, as well as scrutiny of their credit-card charges, their travel and their visits to neighborhood gathering places, including mosques."

"The campaign, which has also involved efforts to recruit the suspects' friends and family members as government informers, has raised alarm from civil liberties groups and some Arab-American and Muslim leaders. The men are suspected of ties to Al Qaeda or other groups affiliated with Osama bin Laden's terrorist network."

"Still, the F.B.I. has acknowledged that it has no evidence of any imminent terrorist threat posed by the so-called sleeper cells connected to Al Qaeda."

Nor is there any evidence of a sleeper cell in the U.S. with capablilities like the one that committed the attacks of September 11.

Law enforcement officials also concede now that the threat of Jose Padilla, the suspected "dirty bomber" was blown out of proportion. "Justice Department officials have backed away from their initial suggestion that they had compelling evidence linking him to a plot to build an explosive radiological device known as a dirty bomb."

Terrorism experts estimate that ten to twenty thousand Muslims trained at Al Qaeda camps. The U.S. is trying to identify all of them. So far, they have identified several hundred around the world who they believe might pose a threat.

"Some law enforcement officials say that when they have detected Qaeda loyalists in the United States since Sept. 11, they have tended to be hapless malcontents and not disciplined terrorists. "They are hangers-on and wannabe terrorists for the most part," said one official, adding, in reference to the leader of the Sept. 11 plot, "Mohammed Atta wouldn't have asked most of these guys to take out his trash."

The electronic surveillance has been accomplished through FISA court orders. FISA orders allow wiretapping and e-mail seizures for intelligence gathering purposes and do not require compliance with the stricter standards of the Fourth Amendment that is required in criminal investigations. In other words, there is no requirement that probable cause be estbablished that the person to be intercepted is involved in criminal activity.