This is the first time coordinated direct actions of civil disobedience have happened," Barbra Bearden, communications manager for the group Peace Action, said.

"People who have never done this kind of action are stepping up and deciding now is the time to do it."

But President George W. Bush strongly signaled yesterday that he will not order US troop withdrawals beyond those already planned because he refuses to "jeopardize the hard-fought gains" of the past year.

Antiwar protesters shout slogans after being arrested by police after attempting to block an entrance of the Internal Revenue Service in Washington, DC, March 19, 2008. The demonstrators are protesting the fifth anniversary of the US invasion of Iraq. [Agencies]

The president spoke at the Defense Department to mark the anniversary. He gave a strong defense of his decision to go to war and continue it and linked the fighting there to the global battle against al-Qaida.