A father who was found dead following a house fire that also killed his six-year-old son was discovered hanging in an adjacent garage, Avon and Somerset Police said.
Police are investigating claims that the blaze which killed Christopher Townsend, who worked for the BBC's Casualty series, and his son, Charlie, six, was started deliberately.
Charlie died in hospital after emergency services were called to the house in Long Ashton, North Somerset.
Neighbours said Mr Townsend had split from his wife Paula, who lives with another son in the village, within the last year.
An Avon and Somerset Police spokesman said: "We are working closely with the fire services and the home is currently cordoned off as a crime scene. These are very early days in our investigation."
He also said the bodies would not be formally identified before the results of a post-mortem are issued on Friday.
The spokesman added: "Firefighters entered the two-storey semi-detached house where they found the body of a man.
"A six-year-old boy was found in an upstairs room. He was taken to hospital where sadly he died a short while later.
"Weston Road in Long Ashton has been shut to traffic and is likely to be closed for some considerable time. Police will be liaising with fire investigators in order to try to determine the cause."
The BBC confirmed Mr Townsend had been a freelance set designer for "some years".
