Doctors have determined that John Demjanjuk, suspected of having been a guard in a Nazi death camp, is fit to stand trial as an accessory to murder, clearing the way for formal charges to be filed this month, prosecutors said Friday. He has been in custody in Munich since arriving there May 12 after losing a court battle to stay in the United States. The 89-year-old retired auto worker is accused of being an accessory to murder in 29,000 cases at the Sobibor camp in Nazi-occupied Poland during World War II. Efforts to prosecute the Ukrainian native began in 1977 and have involved courts and government officials from at least five countries on three continents. The charges carry a maximum sentence of up to 15 years in prison in Germany.