Nobody will be prosecuted over a reported dog attack at Gravelly Hill in Caterham on 12 January, Surrey Police have said.
A 28-year-old woman, who has not yet been named by police, is thought to have been walking a number of dogs when she was set upon.
She was later pronounced dead at the scene.
Senior investigating officer, Detective Inspector Josephine Horner, said: “This is a tragic incident in which a young woman lost her life.
"I know it has caused real concern locally and I thank the community for bearing with us whilst we conducted our inquiries.
"The criminal investigation has now concluded and the information we have gathered will be passed to the Surrey Coroner to assist in the coronial process.
“The dogs continue to be cared for at private kennels to ensure their welfare and their owners are being kept informed.
"We appreciate this is a difficult and uncertain process for them as the forensic work continues.”
Another woman who was injured and was treated for dog bites has since been discharged from hospital.
Richard Bream, who runs the nearby Mardens Kennels, said he had never heard of a dog attack in the area before.
He said: “That particular area, View Point, is an area where professional dog walkers will turn up in their van and take the dogs out and walk them.
“I’ve always felt you see some of these dog walkers have five or six, and they shouldn’t be able to do that.”
A woman walking a border collie past one of the police cordons, who asked not to be named, said she was shocked by the incident.
She said: “It’s a nice circular woodland walk and we’ve never had any issues before. It is so shocking, normal dogs surely wouldn’t do that.”
Anyone with information can contact Surrey Police quoting PR/45230004384
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