Concepcion Picciotto, who demonstrated against nuclear weapons in front of the White House since 1981, died on Monday at a facility for a non-profit that supports homeless women in Washington, D.C. She was 80.There was no known cause of death, according to Peace House-a group that organizes protests at the White House-but Picciotto's health has deteriorated in the past several years.A Spanish immigrant, Picciotto, joined the protest of nuclear disarmament activist William Thomas in 1981.The pair was later joined in 1984 by Ellen Benjamin, whom Thomas eventually married.For 25 years, the self-described peace activist trio maintained a campaign in a symbolic small tent at the gates of the White House. Their objective was complete global disarmament.When Thomas died in 2009, Benjamin was noticeably less active in protests but Picciotto continued her vigil in front of the White House in his honor.The protest and members have been the subject of high-profile documentaries, including Michael Moore's Fahrenheit 9/11.