The chairman of the Senate Homeland Security Committee said Sunday that domestic terrorism is a real and growing danger.
Sen. Joseph I. Lieberman, Connecticut independent, said the political discourse in the United States turns extreme and incendiary at times, and that can lead some people to take radical actions.
Federal authorities report an uptick in the activities of domestic extremist groups in the last year.
Noting the recent bombings in Moscow, Mr. Lieberman said more must be done to protect trains, subways and buses in the United States.
Mr. Lieberman appeared Sunday on NBC's "Meet the Press."
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