Mr. Ashcroft told lawmakers that the authorities need still greater powers to track and pursue terrorists.

He advocates creating a comprehensive government database to track criminals and terrorists.

The current multipoint wiretap standard gives the Government all the means it needs to track terrorists, while protecting the privacy rights of Americans.

We've passed a new antiterrorism law which gives our law enforcement officers the necessary tools to track terrorists before they harm Americans.

"The challenge for intelligence is not to track down known terrorists," he said.

The data was used in a research project on how to track terrorists and other "high-risk" passengers.

And in both cases, doctors said, they were stopped by law enforcement officers armed with radiation detectors used to track possible terrorists.

Federal immigration authorities today began releasing scores of foreign-born men who had been detained in a nationwide dragnet designed to track potential terrorists.

It will track, they said, not only suspected foreign terrorists but also Americans tied to domestic events like violence at abortion clinics.

Still, he acknowledged that it was much harder to use electronic intercepts to track terrorists than the "industrial-sized" targets of the cold war.