A frenzied killer who stabbed his friend 60 times before setting his flat alight was locked up indefinitely.
In "a truly tragic case", Daniel Osobu, 30, knifed father-of-one Antonio Tommaso repeatedly in his cheek, neck and chest at his home in New Barnet.
The 49-year-old, who lived alone, lay dead for seven days before his killer came back to torch the top-floor apartment in an attempt to destroy the evidence.
The pair had been friends and Osobu blamed the fatal attack on "demonic voices" which insisted he was going to be kill.
At the Old Bailey Judge Peter Rook imposed an indefinite hospital order under the mental health act.
He commended next door neighbour Matthew Chantry, an off-duty police officer who risked his life trying to save the victim before evacuating the rest of the building.
Osubo, who has a history of mental illness, was diagnosed with paranoid schizophrenia and had refused to take his medication around a month before the stabbing.
"It is indeed a tragedy that it was not appreciated at the time of this terrible episode that you represented such a risk of violence," said the judge.
"In my view you remain a substantial risk to yourself and others."
Mr Tommaso was well-known in his local community and was often seen cycling around the area. He was unemployed and had a daughter who lived with his former partner in America.
Prosecutor Simon Denison QC told the court that the defendant was suffering from a psychotic episode at the time of the attack.
Osobu admitted stabbing his victim to death and return later to set fire to the house to avoid arrest after hearing voices in his head.
He has suffered from mental health problems, including schizophrenia, psychotic episodes and depression from the age of around 20.
Osobu, of Stanmore, pleaded guilty to manslaughter on the grounds diminished responsibility and reckless arson in May 2014.
