A German male nurse was charged on Thursday with killing 29 patients by lethal injection after an investigation which has involved digging up dozens of graves. The 26-year-old man will face trial on 16 counts of murder, 12 counts of manslaughter and one count of manslaughter with the victim's consent. The nurse, who has already been in custody for more than one year, also faces one count of attempted murder, two counts of causing bodily harm and five theft charges, the prosecutor's office in the southern German town of Kempten announced. The trial is expected to take place in 2006. Investigators dug up 42 graves in the search for evidence. Around 80 percent of the alleged victims were aged 75 or older, although the youngest was 40, prosecutors said. The accused is expected to argue he was acting out of compassion for the victims. Police began investigating the nurse when drugs were reported missing from a clinic in Sonthofen where he worked.