BBC News Published image copyrightMet Police image captionTheodore Johnson met Angela Best while he was on unescorted leave from a secure mental hospital A woman who was murdered by a man who had previously killed two other partners would "probably" be alive if authorities had investigated their relationship, a coroner has found. Theodore Johnson, 67, strangled ex-girlfriend Angela Best in 2016. St Pancras Coroner's Court heard they had been together for 20 years but nobody who was monitoring him suspected he was in a relationship. Coroner Mary Hassell concluded Ms Best had been unlawfully killed. The victim's family said they "can never recover from what we have gone through following the brutal murder".