Cuba ? A legal aid group representing Guantanamo Bay detainees condemned the U.S. military prison Tuesday as an “abomination” and called on Washington to close the facility, which opened five years ago this week.

Michael Ratner, president of the New York-based Center for Constitutional Rights, said reports of abuse inside Guantanamo and the prisoners’ lack of access to the U.S. justice system damages America’s international standing. The center represents hundreds of Guantanamo detainees.

To mark the anniversary, demonstrations are planned Thursday in New York, London, Sydney, Australia, and other cities as well as dozens of small towns in the United States and Britain.

A delegation including Cindy Sheehan, who became an anti-war activist after her soldier son was killed in Iraq, plans a protest in Cuba outside a gate leading to the U.S. Navy base. She will be joined by Asif Iqbal, a British Muslim who was held at the prison for 2 1/2 years.