The victim's estranged husband is among those arrested.

Mother-of-two Geeta Aulakh, 28, was attacked in Greenford, northwest London, on Tuesday as she made her way to her childminder's home.

She was found with head injuries and a severed hand, according to witnesses.

Aulakh was taken to hospital but died a few hours later. A post-mortem has since revealed that she died of a severe head injury.

Detective Chief Inspector Andy Chalmers, who is leading the inquiry, said: "When the victim was found we know that a lot of people were in the street and that several people may have tried to administer first aid before the police or ambulance arrived.

"These people left the scene before speaking to police and I would ask that anyone who was there, or anyone else who has information about the incident, call us in the strictest of confidence."

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