Rumsfeld: 'We've got a very serious problem'

WASHINGTON (CNN) -- International terrorists working to kill "thousands and thousands" of men, women, and children in the United States will someday gain access to chemical and biological weapons from nations that support them, U.S. Defense Secretary Donald Rumsfeld said Thursday.

"We've got a very serious problem," Rumsfeld said on CNN's "Wolf Blitzer Reports."

"There's a lot -- hundreds of well-trained terrorists around the world in 40 or 50 countries," he said. "They are determined to kill thousands and thousands of people, innocent people -- men, women, and children -- as they did on September 11. They're working to do that."

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He continued, "We do have information that they have been trying to get [weapons of mass destruction], particularly chemical and biological, and that the countries that they have relationships with do have these capabilities."

Rumsfeld said Iran, Iraq, Syria, Libya, and North Korea are among those nations. He also mentioned that Cuba has been on the U.S. list of nations that aid terrorist groups.

"We have to expect that global terrorist networks that we know are trying to get these weapons will in fact be successful at some time in the future," Rumsfeld said.

Rumsfeld said the United States is working to prevent terrorist acts of mass destruction by training antiterrorist units in Yemen, the Philippines, and Georgia.

Asked whether terrorist leader Osama bin Laden is still alive, Rumsfeld said he didn't know.

"This isn't our business, the secretary of defense's business, to track down a single individual," he said. "We've never organized ourselves as a law enforcement agency. That is a very difficult thing to do. It's like finding a needle in a haystack."