A law graduate strangled a 59-year-old woman when they were both patients on a psychiatric ward in Rochdale, Greater Manchester.
Telahum Tedola confessed to the killing and told a nurse he attacked Rosalyn McManus because she accused him of being a spy.
Tedola, 36, could face being sent to hospital for life after last week he admitted manslaughter at Manchester Crown Court, the Rochdale Observer newspaper reported.
Alistair Webster QC, who accepted Tedola’s plea of not guilty to murder, said it was clear from psychiatric reports that he was suffering from a serious mental illness.
Tedola, who is being held at Ashworth secure hospital, was remanded in custody until 14 March for sentence.
Judge Andrew Gilbart said: “I require reports from consultant psychiatrists about your condition but the result will be either a sentence of imprisonment or you will be committed to a secure mental hospital.”
At the time of the killing, Ms McManus was an in-patient on the psychiatric ward at Birch Hill Hospital where Tedola was also a patient.
Tedola was admitted as an emergency after staff at a hostel where he was living were concerned about his health and his claims he was being persecuted, the Rochdale Observer reported.
Tedola, who came to England in 2005 after getting a law degree in Ethiopia, strangled Ms McManus in the women’s TV lounge one evening last August.
Tedola was seen coming out of the lounge holding a black belt which was in a loop and told a nurse he killed Ms Manus after she called him a spy.