Ashcroft: Terrorists 'poisoning our communities'

WASHINGTON (CNN) -- Terrorists live within U.S. borders "plotting, planning, waiting to kill Americans again," Attorney General John Ashcroft warned Thursday as the nation grappled with an anthrax crisis that may be linked to last month's deadly hijackings.

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Speaking before a gathering here of the nation's mayors, Ashcroft again warned of the possibility of further attacks.

"Today's terrorists enjoy the benefits of our free society even as they commit themselves to our destruction," Ashcroft said.

"They live in our communities, plotting, planning, waiting to kill Americans again. They have crossed the Rubicon of terror with the use of biological agents.

"We cannot explicitly link the recent terrorist attacks to the September 11 hijackers," Ashcroft said.

"Yet, terrorists -- people who were either involved with, associated with, or are seeking to take advantage of the September 11 attacks -- are now poisoning our communities with anthrax."

New details are emerging about the nature of the anthrax whose spread through the mail has infected 13 people, three of whom have died.

The latest included what the State Department called an anthrax infection in one of its employees who worked in a Virginia mail room. The man was diagnosed inhalation anthrax.

There are numerous other possible cases of anthrax, among them a second New York Post employee with possible skin anthrax and a second NBC employee with the same. And traces of anthrax showed up in two new locations in a Senate building.

Authorities have identified three anthrax-laced letters: one sent to a Senate office, another to NBC News and a third to the New York Post. All three letters were postmarked in Trenton, New Jersey.

Postal workers who handled those letters are among those infected, along with people who handled the mail at its destinations.

The anthrax spores found in the letter received at Senate Majority Leader Tom Daschle's office were "more dangerous" than those received at the other sites, Homeland Security Director Tom Ridge said at a White House news briefing.

Earlier, Daschle told reporters the bacteria may be "a little more aerosolable," a condition that would make the anthrax easier to spread and inhale. But he said the type of anthrax was a "common variety" that was "treatable."

As for the source, Daschle said that experts have told him that three countries made this kind of anthrax.

"It's made in the United States, it's made in Iraq and it's made in Russia ... I think those three countries are the most likely areas where you would find anthrax like this," Daschle told reporters.

Sources cautioned, however, that investigators have not concluded the anthrax-letters are state-sponsored. They could, for example, be the result of anthrax sold on the black market.

A government official told CNN that tests conducted at a military research lab in Maryland indicate the anthrax found in a letter delivered to Daschle was high grade and shows the presence of additives.

The source described that as a highly sophisticated technique to reduce the electrostatic charge and free the spores to travel freely through the air and make them easier to lodge in the lungs.

In the Hart Senate Office Building, investigators found traces of anthrax in two new locations Thursday, according to Capitol Police spokesman Lt. Dan Nichols. He said traces of anthrax were found on a ventilation filter on the ninth floor and on a stairwell between the eighth and ninth floor.

The confirmed anthrax infections include one New York Post employee diagnosed with cutaneous anthrax, as have an NBC News employee, the infant son of an ABC News producer, a CBS News employee and two New Jersey postal workers.

The trail of the Daschle letter -- and letters received at NBC News and the New York Post -- have been traced to a mail processing facility in New Jersey.

Several patients in New Jersey, New York and Washington are being evaluated for possible anthrax infections, including a New Jersey postal worker who may have inhalation anthrax and a Capitol Hill journalist who was standing outside Daschle's office when the letter was opened.

But Dr. John Eisold, the Capitol Hill physician, said he doubted the case would turn out to be anthrax and said the woman should "turn out to be fine."

In New Jersey, officials said they would expand testing for anthrax contamination to include a postal distribution center in Carteret, about 25 miles away from Hamilton Township. They believe the Daschle letter passed through the Carteret facility after it was postmarked in Trenton.