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Cheney: 'Reasonable' to assume anthrax cases linked to terrorists

Cheney appeared Friday evening on the PBS news program "The NewsHour with Jim Lehrer"

WASHINGTON (CNN) -- Vice President Dick Cheney said Friday it is "reasonable" to assume the recent anthrax cases in the United States are linked to the September 11 terrorist attacks, because Osama bin Laden's terrorist training manuals teach "how to deploy these kinds of substances."

"If I received a letter that I didn't know where it came from, didn't recognize the sender, ... then I'd be suspicious of it. I'd have it checked," Cheney said in an interview on PBS' "The NewsHour with Jim Lehrer."

He urged Americans to be "more alert as a society" and to contact authorities if anything seems suspicious.

"We just need to be more sensitive that there are, in fact, people in our midst who wish us ill," said Cheney.

The vice president, who has been at a secure location for national security purposes since Sunday's bomb campaign over Afghanistan began, said the United States knew over the years that bin Laden "tried to acquire weapons of mass destruction," including chemical and biological weapons.

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Asked about possible links between the September 11 terrorist attacks and the recent anthrax cases, Cheney said bin Laden has trained his al Qaeda fighters for such attacks and handling of chemical and biological weapons.

"When you start to piece it all together, and again we haven't completed the investigation and maybe it is coincidence, but I must say I'm a skeptic," he said. "I think the only responsible thing for us to do is to proceed on the basis it could be linked."

Health officials and the FBI have said there is no evidence yet of any links between the September 11 attacks and the anthrax cases. Four people -- three in Florida and one in New York -- have been exposed to anthrax in the past 1 1/2 weeks, including one man who died.

Cheney said the U.S. has received numerous threats of more terrorist attacks, but nothing specific.

"It will reference what happened on September 11, and talk about another event. It may not be any more precise than that," he said.

He said there is no reason to believe the deadly attacks on the World Trade Center and Pentagon were a "one-off event."

"In fact, we have to assume it will happen again," he said. "The events of September 11 marked a watershed in American history. It was a time when the U.S. homeland now is open to attack in ways that we had only speculated about before. And we know that there are threats out there."

The vice president said Pennsylvania Avenue, which runs right in front of the White House, should remain closed to through traffic, especially amid the current terror climate.

"Pennsylvania Avenue ought to stay closed because ... if somebody were to detonate a truck bomb in front of the White House, it would probably level the White House and that's unacceptable."

Cheney said it is believed more terrorists are in the United States. He said one person arrested in Minnesota in August may have been preparing to be the fifth terrorist on one of the hijacked flights.

Cheney noted that there were only four hijackers aboard the flight that crashed in a field in Pennsylvania.

"We think we may have that individual in custody, but we don't know for sure," He said.

"We're doing everything we can to wrap them up as quickly as possible. But I think the only safe assumption is there may very well be others here," said the vice president.