A woman found dead in her family home in Twickenham was killed by "multiple stab wounds" while her husband and two sons died from falling from a height 80 miles away, a post-mortem examination revealed.
The bodies of two young boys and their father were discovered at the foot of cliffs on the south coast an hour before their mother was found dead at the home they shared in South Road on Monday evening (March 5).
Post-mortem examinations for all four of the deceased concluded on Thursday (March 15).
The cause of death for the 47-year-old woman, believed to be the two boys' mother, was given as multiple stab wounds at Kingston Mortuary on Monday (March 12).
An examination of the at the same mortuary, on Tuesday (March 15) showed that the man died from multiple injuries consistent with falling from height.
The same cause of death was given for the two young boys at St Thomas' Hospital on Thursday (March 15).
Police had been called just before 6pm on Monday (March 5) to South Road in Twickenham following concerns raised about the welfare of the family.
A Metropolitan Police spokesman said: "A woman aged 47 was found dead at the scene with stab injuries.
"Detectives quickly sought to establish the welfare of her husband, aged 57, and two children aged seven and 10, and carried out a number of urgent enquires.
"Just before 5pm, the bodies of a man and two young boys were discovered at Birling Gap seafront, East Sussex. Sussex Police later contacted the Met.
"Whilst formal identification awaits, police believe that they are the deceased woman’s immediate family."
Next of kin have been informed.
No arrests have been made and the Met said officers are not 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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