HAVANA (AP) — A leader of one of Cuba's largest dissident groups has been held incommunicado for a week in the eastern part of the country, the human rights organization Amnesty International said Friday.

Amnesty called on the Cuban government to allow family members of Jose Daniel Ferrer Garcia to visit him at a jail in Santiago de Cuba and let him hire a lawyer of his choice.

The leader of opposition group Patriotic Union of Cuba and his colleague Ebert Hidalgo Cruz were arrested Aug. 3 following a traffic accident involving a plain-clothed security official, the group said. It said only Hidalgo has been allowed a family visit.

The U.S. State Department also expressed concern. "No family visit, no lawyer, no due process, no justice," Francisco Palmieri, a principal deputy assistant secretary in the Bureau of Western Hemisphere Affairs, said in a tweet.

Ferrer was among 75 dissidents imprisoned in a March 2003 crackdown. He was released in March 2011.

The Cuban government had no immediate comment.