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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A gang of robbers who dressed in burkas to stage raids on high-end stores in London have been convicted today.
The retrospective is so in-demand the museum will open its doors all through the night for the first time since it opened in 1857.