Robert Torto, 33, who was charged just a month after a series of arson attacks in April 2006, originally denied involvement but pleaded guilty at the Old Bailey this month.
Torto, from Stockwell, admitted setting fire to the Price Cutter convenience store in April 2006 (C-Store, May 5 2006). Retailer Khizer Hayat died inside the Kennington store while his colleague Hamidullah Hamidi died six days later. Two further members of staff escaped with minor injuries.
Torto, who was suffering from paranoid schizophrenia, was ordered to be held indefinitely in a secure hospital. He also admitted one count of arson but two further firebomb attacks, in Tulse Hill and South Norwood, were allowed to lie on file.
Police discovered disturbing handwritten notes when they raided Torto's home before his arrest last year. Torto, who was sent to a psychiatric hospital in 2001 but released just two months later, spoke of targeting shops, churches, mosques and hospitals.
DCI David Garwood, who led the investigation, said: "Robert Torto clearly had a mission in mind and that was to attack people from a number of different communities with crude yet dangerous home-made accelerant devices. What remains unclear is his motive."