There are more than 1,100 desaparecidos (disappeared persons) in Chile and one of them is a U.S. citizen - Boris Weisfeiler. A Russian-born mathematics professor at Pennsylvania State University, Weisfeiler vanished while on a hiking trip near the border between Chile and Argentina in the early part of January 1985. After a quick and cursory investigation, Chilean authorities concluded that Weisfeiler had drowned in the Nuble River during his trip.
Declassified U.S. documents tell a different story. According to an informant, Weisfeiler was detained by Augusto Pinochet's soldiers, presumed to be a Russian or Jewish spy, and taken to the mysterious German colony Colonia Dignidad. The declassified U.S. documents show that the U.S. Embassy personnel did not do enough to ascertain the fate of Weisfeiler, the only missing U.S. citizen in Chile. As consul Jayne Kobliska stated more than a year after Weisfeiler's disappearance in a memo from April 1986, "the real danger in this case is that we will delay action until it is too late to either save Weisfeiler's life or to determine the true circumstances of his death." <snip>
On January 25, 2005 President of the Chilean Supeme Court, Marcos Libedinsky, anounced that the Supreme Court has set a six-month deadline for the completion of hundreds of human rights investigations relating to crimes allegedly committed by former members of Augusto Pinochet's military government during 1973 -1990. The ruling orders that by July investigators must either file charges or terminate the inquiries in 365 cases against former members of the armed forces. The deadline will not be kept in cases where there is a strong reason for an extension, Libedinsky said.
http://boris.weisfeiler.com/index.html<edit: add third paragraph>