German investigators said Tuesday they believe a nurse in their custody killed 29 of his patients before he was arrested last July. The 26-year-old suspect, who has not been named, had already admitted to giving fatal injections to 16 people in his care, most of them elderly, in what he said were mercy killings. Toxicological analyses of the bodies of 42 deceased former patients of the suspect revealed that an additional 13 showed signs of an overdose of medication, authorities in the southern German town of Kempten said. The accused now faces charges of murder, manslaughter, killing on demand as well as attempted grievous bodily harm. The alleged victims include 17 women and 12 men between the ages of 40 and 94 who died in the period from February 2003 to July 2004. The prosecutor's office said the health of the deceased just before they died would play a significant role in the case because of the nurse's claims he was alleviating their suffering. A trial date has not yet been set.