A 19-year-old man has admitted killing an American tourist and wounding five other people during a stabbing rampage in London last year. Zakaria Bulhan, a Somali-Norwegian who moved to Britain as a child, had been charged with murder and attempted murder but a court accepted his guilty pleas to manslaughter and wounding at a hearing Monday, the Guardian reports. The court was told Bulhan was having an acute episode of paranoid schizophrenia and believed the devil was talking to him when he killed Darlene Horton, a retired teacher from Florida who was visiting London with her husband, on Aug. 3. Bulhan will be sentenced Tuesday and could be sent either to prison or a mental hospital, the BBC reports. (More United Kingdom stories.)