Police have named the man as Thomas Baird. He'd been stabbed and was pronounced dead in the early hours of Saturday after the blaze at his home in Westerdale, Hemel Hempstead, Hertfordshire.
A post-mortem examination carried out yesterday concluded that the 63-year-old died of trauma to the head and neck, and stab wounds to the chest.
A 30-year-old man from Hemel Hempstead, who was arrested on suspicion of murder on Saturday, remains in police custody.
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"All it takes is for somebody to see me - and I could just die, just like that. I could want to go to the shop and not come home."
Before the killing, Peters searched the internet for "serial killers", "treatment of child killers in prison" and "premeditated murder".
Arriva Rail North, Greater Anglia and South Western Railway are all affected.