A woman died of shock caused by blood loss as a result of being bitten by her daughter's dogs, a post-mortem examination has revealed.
71 year old Gloria Knowles was found dead at a house in Morden on Tuesday evening.
Five dogs were seized and police cordoned off two adjoining houses.
No arrests have been made in connection with the attack.
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Officers believe the three assaults are linked and are appealing for information about the suspect.
Nine addresses in Lewisham were searched and 13 arrests made early on Tuesday morning in a planned, intelligence-led operation.
The Purple Rain singer died in April 2016