International peace activists marched to the Cuban military zone wrapping around the U.S. naval base at Guantanamo Bay on Thursday to demand closure of the U.S. military prison for terror suspects five years after the first detainees arrived.

The dozen protesters, including relatives of one of the prisoners and American "peace mom" Cindy Sheehan, walked along a lonesome asphalt highway connecting the Cuban city of Guantanamo to the military zone. Sheehan wore a peace sign medallion around her neck.

They chanted "Gitmo prison is a source of shame, no more torture in our name" and held signs saying "due process is overdue" and "there are no justice-free zones." The brother of British citizen Omar Dehayes carried a large color photograph of the detainee that said "justice for my brother."

It was not immediately clear how close the group would get to the actual base, where the U.S. military is holding about 395 men on suspicion of links to Al Qaeda or the Taliban, including about 85 who have been cleared to be released or transferred to other countries. The military says it wants to charge 60 to 80 detainees and bring them to trial.

U.S. Army Col. Lora Tucker, a spokeswoman for the detention center, said the military had no plans to acknowledge the protest or increase security at the gate, which is located at a distance from the prison camp on the other side of a hill.

"Nothing changes for us based on a demonstration being held somewhere in Cuba," she said, adding that Thursday was "a normal work day" at the naval base with no special events planned to mark the anniversary.

The protest outside the base coincided with another demonstration of about 100 people in London outside the U.S. Embassy. Wearing orange, Guantanamo-style inmate outfits and surgical masks, the protesters formed eight long rows on a nearby street. Three "guards" wearing green camouflage outfits walked among them, shouting orders for them to stand up or kneel down.

The group in Cuba planned to read the names of all the men still held at the prison.

A day earlier, the activists screened a film for Guantanamo city residents about former prisoners at the U.S. military base, including Asif Iqbal, a British Muslim detainee released two years ago who returned to Guantanamo to join the protest.

"We should be able to shut down the U.S. prison," Medea Benjamin, who organized the protest through the California groups Global Exchange and Codepink, said before the screening of the movie "The Road to Guantanamo," prompting a standing ovation by several hundred Cubans at the event. "Let's dream about closing down the base completely."

Residents of Guantanamo largely resent the presence of the U.S. base, which their government considers a violation of the communist-run nation's sovereignty.

Zohra Zewawi, the mother of detainee British citizen Omar Dehayes, traveled from the United Arab Emirates with another son, Taher Deghayes, to join the protest. She says her son had been tortured and blinded in one eye since he was imprisoned in September 2002 and still has not been charged or tried.

Sheehan, of Vacaville, California, became an anti-war activist after her 24-year-old son Casey was killed in Iraq. She drew international attention and was dubbed the "peace mom" after she camped outside of U.S. President George W. Bush's Texas ranch.

The protesters arrived in Guantanamo from Havana on Tuesday night and on Wednesday held a daylong international conference that featured members of their group and Cubans from Guantanamo, many of them high school and university teachers.

"They feel a lot of pain because their city is known for the prison," Benjamin said of the Cuban teachers.

During the conference, peace delegation member Adele Welty, who lost her firefighter son in the Sept. 11, 2001, terror attacks, expressed empathy with Zewawi and other mothers of men held at Guantanamo prison.

Welty said that in the case of her son Timothy, "I have been assured that it was over quickly, that he did not feel the tons of concrete that tore his body apart.

"But for five years, (the inmates') mothers have lived with the images of them being torn apart from torture," Welty said.