Officials: 200 in U.S. under 'constant' surveillance

WASHINGTON (CNN) -- Investigators trying to uncover terrorist cells have about 200 people in the United States under "constant" surveillance -- individuals whose names were uncovered as a result of information from Abu Zubaydah and other sources, officials familiar with the terror investigation told CNN.

Zubaydah, the head of operations for al Qaeda, was taken into custody in March in Pakistan, and is the highest-ranking Osama bin Laden operative now in the hands of authorities.

Officials confirmed to CNN that Zubaydah continues to provide good information to investigators. During his capture, investigators said, they also recovered disks and documents that have been helpful in determining the focus of the terror investigation in the United States.

Included in the intelligence gathered were names of suspected terrorists, these officials said. That information and other intelligence has led officials to some mosques and about 200 individuals in the United States. Those people, the sources said, are under "constant" surveillance.

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The surveillance is being conducted by members of joint terrorism task forces throughout the country. CNN has previously reported that individuals are under surveillance in Seattle, Chicago, Detroit and Atlanta.

The mosques under scrutiny are in at least nine cities across the United States, and include ones in Laurel, Maryland, and San Diego, where some of the September 11 hijackers lived. Other mosques being watched are in Jersey City, New Jersey; Cleveland, Ohio; Norman, Oklahoma; Fort Lauderdale and Pembroke Pines, Florida; Falls Church, Virginia; and Tucson, Arizona.

Policy changes put in effect after the September 11 attacks allow investigators to watch religious institutions, even if there is no evidence of a crime. Investigators say they are trying to identify members of hidden terrorist cells, or support personnel in the United States.

According to documents released this week, one suspected terrorist who has had dealings with Zubaydah is Jose Padilla, an American citizen currently being held as an enemy combatant. Padilla is accused of planning to build and detonate a radioactive "dirty bomb" within the United States.

The documents allege that while in Afghanistan in 2001, Padilla and an unnamed associate met with Zubaydah to propose a plan to conduct terrorist operations within the United States. Zubaydah then directed Padilla and his associate to travel to Pakistan for training.

In a previously classified memo, Michael Mobbs, a special adviser to the Defense Department, wrote, "Padilla and his associate conducted research in the construction of a 'uranium-enhanced' explosive device. In particular, they engaged in research on this topic at one of the al Qaeda safe house in Lahore, Pakistan."

Meanwhile, two other top al Qaeda figures, at a level just below Zubaydah, also remain in custody. They are Abu Zubair al-Haili and Ibin al-Shaykh al-Libi.

An official said "useful information" is being obtained from them, also. Sources have told CNN that al-Libi is in Egyptian custody but have been unwilling to say where al-Haili is being held or by whom.

--CNN Justice Correspondent Kelli Arena and National Security Correspondent David Ensor contributed to this report.