by Justin Rood

The FBI now keeps a list of over 900,000 names belonging to known or suspected terrorists, the American Civil Liberties Union said today.

If that number is accurate, it would be an all-time high, exponentially more than the 100,000 names on the list several years ago. But the number needs to be taken with a grain of salt: after all, the ACLU doesn't keep the list, the FBI does, and the bureau doesn't generally like to talk about it. (Indeed, the FBI has not yet responded to a request for comment for this post.)

But if the ACLU's figure isn't accurate, it's also unlikely to be off by that much. Last September, the ACLU notes, the Department of Justice's Inspector General reported the FBI watch list was at 700,000 names, and growing at 20,000 names per month.

The ACLU says they "extrapolated" from those figures to determine the list's current size. ACLU's Barry Steinhardt added that the group had spoken privately with people familiar with the watch list, who told them the 900,000 figure was not outlandish.

In the past, The FBI has told ABC News that the size of its watch list is classified. Despite that, both the bureau and the DoJ Inspector General have published the total figure in unclassified reports.

There's no doubt the FBI's list is growing: just last June, ABC News reported it was at 509,000 names, based on information in an unclassified FBI budget document.

But strangely, the list may be growing not because of swelling legions of foreign terrorists. Instead, it appears the FBI may be adding tens of thousands of names belonging to U.S. persons it suspects of being domestic terrorists -- people who have no known ties to international terrorist organizations.

A separate entity, the National Counterterrorism Center (NCTC), keeps a list of all names believed to belong to terrorists linked to international terror groups. That list, which was at 100,000 names in 2003, grew to 465,000 names by last June - but since then has grown only modestly, according to NCTC spokesman Carl Kropf. Today, Kropf said that list stands at roughly 500,000 names. (Unlike the FBI, the NCTC does not maintain that the size of its watch list is classified information.)

The FBI takes that list and adds to it a new collection of names which belong to U.S. persons believed to be domestic terrorists: people who have links to terrorism but not to any international group.

Last June, the NCTC was responsible for putting 465,000 names on the watch list, and the FBI appeared to add an additional 44,000. By September, extrapolating from the DoJ Inspector General's report, the FBI's contribution appears to have grown to somewhere north of 200,000 names.

Today - if the ACLU is to be believed - the FBI's contribution may be as high as 417,000 names. Which would raise a new question: Where are so many domestic terrorists coming from? Or do they simply use more aliases than foreign terrorists?

Update: The FBI responded late Wednesday afternoon. Spokesman Chad Kolton did not dispute the ACLU's figure, but noted that the watch list contains names, aliases and name variations for individuals. The number of people on the watch list, he said, was around 300,000, and only 5 percent are U.S. persons. Kolton noted that the list is "regularly reviewed for accuracy." Last year the bureau removed 100,000 records "related to people cleared of any nexus with terrorism," Kolton said.
© 2007 ABC News