A family of four, including two young boys, have been found dead in separate locations.
The mum, believed to be in her 40s, was found stabbed to death at the family's Twickenham home on Monday (March 5).
Police believe her 57-year-old husband and two sons, aged seven and 10, were found dead later that day on the East Sussex seafront - formal identification is awaited.
Metropolitan Police attended the Twickenham address in South Road at 5.54pm on Monday after concerns were raised about its residents.
According to the Met a woman was found dead at the scene having suffered stab wounds.
The Met quickly sought to trace her family and Sussex Police confirmed it had found the bodies of a man and two young boys at Birling Gap seafront, Eastbourne, just before 5pm.
While formal identification awaits, police believe the bodies were those of the dead woman’s husband and two sons.
A car was recovered nearby by Sussex Police and a crime scene remains in place at the Twickenham address.
An investigation into the deaths has been launched by the Met's Homicide and Major Crime Command and is being supported by Sussex Police.
Post-mortem examinations for all four individuals will take place in due course.
The family's next of kin have been informed and no arrests have yet been made as enquiries into what happened continue.
Police are not currently looking for anyone else in connection with the investigation.
Anyone with information is asked to call the Metropolitan Police on 0208 721 4005, or locally to Sussex Police on 101 quoting Operation Glasson.
You can also call Crimestoppers anonymously on 0800 555 111.
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