Larry Mefford, assistant FBI director for counterterrorism, said Thursday that authorities "feel a lot more confident" they know the identities of dozens of members of the al Qaeda terror network than they did shortly after the attacks of Sept. 11, 2001.
"I don't want to say that we know where they all are," Mefford told reporters after testifying before the Senate Judiciary terrorism subcommittee.
Mefford said the investigations in 40 states run "the whole gamut" from people positively identified as al Qaeda operatives to uncorroborated tips from citizens.
"We know this: The al Qaeda terrorist network remains the most serious threat to U.S. interests both at home and overseas," Mefford told the panel. "That network includes groups committed to the international jihad movement and it has demonstrated the ability to survive setbacks."
Asked if he believed such a sleeper cell could be poised for a new attack on the scale of Sept. 11, Mefford said, "Not that I'm aware of."
One difficulty is that many al Qaeda members use multiple aliases and "jihad" names that are difficult to track. Mefford said the FBI earlier this year found the true identity of one suspected cell member: Adnan G. El Shukrijumah, a Saudi-born man with Florida ties who is the subject of a global manhunt.
"We don't know where he is," Mefford said. An FBI notice on Shukrijumah indicates he uses the aliases Abu Arif; Ja'far Al-Tayar; Jaffar Al-Tayyar; Jafar Tayar; Jaafar Al-Tayyar, and is wanted as a material witness and suspected of making threats against the United States.
The FBI has had greater success in finding people suspected of providing logistical or recruiting help to al Qaeda. Mefford cited as an example last week's guilty plea by Ohio trucker Iyman Faris, who admitted to conducting surveillance for a possible attack on the Brooklyn Bridge and plotting to derail trains.
"I know the logistical cells are here," Mefford told reporters. "The question is whether the most dangerous cells are here."
Earlier this week, President Bush designated as an enemy combatant Ali Saleh Kahlah al-Marri, a Qatari man living in Illinois who the government claims provided financial and other support to new al Qaeda arrivals in the United States. He has been in custody since December 2001 and was charged recently with bank and identity scams before being removed from the court system and placed in a military jail.
Mefford told the Senate panel that arrests of senior al Qaeda leaders and disruption of its sanctuary in Afghanistan have made it more difficult for the organization to mount major attacks.
The FBI is concerned that could lead to more random, smaller-scale attacks against lightly secured targets.
He also said that al Qaeda continues efforts to recruit U.S. citizens and non-Arab operatives who could more easily escape detection and slip through new security measures at U.S. borders.
"They understand the benefits of having this type of asset, somebody who can travel under the radar screen," Mefford said.
Sen. Charles Schumer, D-N.Y., raised several questions about whether Muslim clerics are spreading a version of extreme fundamentalist Islamic teachings in American prisons and among Muslims in the U.S. military.
Schumer said this interpretation of Islam, known as Wahabbism, has spread from Saudi Arabia and preaches "hate, violence and intolerance" toward moderate Muslims, Jews and Christians. Most al Qaeda members subscribe to these teachings, he said.
"My fear is, if we don't wake up and take action now, those influenced by Wahabbism's extremist ideology will harm us in as of yet unimaginable ways," Schumer said.
Mefford said that the FBI and Bureau of Prisons, along with state corrections officials, are actively working on ways to prevent al Qaeda from recruiting in prisons through proselytizing by Islamic clerics tied to terrorism or extremist teachings.