SAN JUAN, Puerto Rico (AP) - Two Yemeni men say they were held in solitary confinement in secret, underground U.S. detention facilities in an unknown country and interrogated by masked men for more than 18 months without being charged or allowed any contact with the outside world, Amnesty International charged Wednesday. Amnesty and human rights lawyers argued that the report added to long-standing claims that the United States has held "secret detainees" in its war on terror. "We fear that what we have heard from these two men is just one small part of the much broader picture of U.S....