An 87-year-old woman has died in hospital after she was assaulted last weekend, Surrey Police have said.
Officers said Rosemary Hill was attacked from behind on Warren Road in Reigate on Sunday.
After the incident at 5.40pm, Ms Hill was taken to hospital with serious head injuries but later died.
Specialist officers are now supporting her family.
A 45-year-old man from Reigate was arrested on suspicion of attempted murder.
He was later detained under the Mental Health Act and bailed. Surrey Police said he remains in hospital.
Detectives are appealing for witnesses who were in the areas of Warren Road, Holmesdale Road, Alma Road and Wray Park Road with the junction of Alders Road between 4pm and 7pm.
Reigate and Banstead Borough commander Inspector Alex Maguire said: “We have a team of officers and detectives continuing to work hard to establish the circumstances of what appears to be a random and unprovoked attack.
“Our officers are providing support to the victim’s family, I’d ask people to respect their privacy at this difficult time.
“I would like to reiterate that assaults of this nature are extremely rare in this area.
“We’re not linking this assault with any other similar reports and making an arrest has allowed us to progress our enquiries, which are continuing.”
Anyone who has information, including dash camera footage from those areas, is asked to contact the force on 101, quoting Operation Baritone.
Information can also be provided anonymously to Crimestoppers on 0800 555 111.
