Operation Ceasefire, a newly formed coalition of musicians who oppose the war in Iraq, yesterday announced plans for a free, 10-hour music festival on the Washington Monument grounds that will be the centerpiece of a cluster of antiwar activities spanning three days, beginning Saturday, Sept. 24.

The concert, billed as a "cultural resistance" by event organizers, will feature acts including the Washington electronica duo Thievery Corporation -- who are also producing the festival -- country-western crooner Steve Earle, socialist rappers the Coup and punk rock/indie artists Le Tigre performing to urge lawmakers to bring the troops home.

A different type of musical event will take place on the Mall two weeks before Operation Ceasefire's planned festival. Country singer Clint Black will headline the Sept. 11 America Supports You concert in support of the military and the victims of the Sept. 11, 2001, attacks. The concert will follow a Freedom Walk, sponsored by the Department of Defense, which will begin at the Pentagon and conclude by the Mall's Reflecting Pool.

The walk and concert will remind participants "of the sacrifices of this generation and of each previous generation that has so successfully defended our freedoms," Defense Secretary Donald Rumsfeld said in a news briefing announcing the Freedom Walk this week.

The Operation Ceasefire antiwar concert is sponsored by ESL Music (Thievery Corporation's label); the Mintwood Media Collective; the New York-based United for Peace and Justice, a coalition of 1,300 antiwar groups; and the DC Anti-War Network.

The events will kick off with a morning rally in front of the Washington Monument, followed by a march through downtown and an "antiwar fair" on the grounds of the Monument, culminating with the concert. On Sunday, there will be an interfaith service and grass-roots training. Monday's activities will feature grass-roots lobbying of 100 legislators as well as a "mass nonviolent direct action and civil disobedience" in front of the White House, event organizers said.

Thievery Corporation's Eric Hilton said he felt compelled to do something to stop the wars in Afghanistan and Iraq ever since "the day after 9/11, when they first started talking about bombing Afghanistan."

"I don't subscribe to the 'love it or leave it' doctrine," Hilton said during the briefing. "I'm American and I love this country, too. I just feel a moral imperative as a human being who happens to be a musician" to do something about the war.

Other acts confirmed for the Operation Ceasefire concert include Bouncing Souls, Ted Leo & the Pharmacists, rock-and-soul band the BellRays, Washington bilingual punkers Machetres, Washington activist and hip-hop artist Head-Roc (one of the event organizers), and Jello Biafra of the seminal punk rock group Dead Kennedys.

"We wanted to focus on groups that were committed to peace and justice," Hilton said, pulling acts from a variety of musical styles including rap, Latin, country, punk and electronica.

But Hilton admitted the group didn't quite get its artist wish list.

Concert organizers sent letters to more than 100 acts, said Washington activist and event organizer Adam Eidinger, but many said they had scheduling conflicts. Organizers would not say who had turned down performance requests.

"We had some delusions of grandeur that we would have some stadium-sized acts," Hilton said.

Eidinger said the collective was still raising funds for the concert, which he estimated would cost between $100,000 and $300,000.

Also involved with the events are Iraq Veterans Against the War and Military Families Speak Out. (The ANSWER Coalition is organizing a Sept. 24 rally in front of the White House.)

"Honestly," said Michael Hoffman, co-founder of Iraq Veterans Against the War, "I feel guilty about what we've done over there." Hoffman said he was a member of the 1st Marine Division, which entered Iraq on March 23, 2003.

"Trying to end this war, in my mind, makes up for some of the damage I've done," he said.

Thievery Corporation's Eric Hilton, left, and hip-hop artist Head-Roc, right, are part of the program at the Washington Monument in late September.