Five children have been arrested on suspicion of murder following the death of an 80-year-old man who was attacked in a park.
Bhim Kohli died in hospital after being assaulted while walking his dog at Franklin Park, in Braunstone Town, Leicestershire, on Sunday evening.
Leicestershire Police said a boy and a girl, both aged 14, and another boy and two girls aged 12, were in custody.
Officers have appealed for witnesses to come forward.
A neighbour of the victim, Deep Singh Kaila, 70, described the incident as "shocking".
He added: "He was a very nice guy. He was always there, working in the allotment. Everyone knows him."
Nick Brown, leader of Braunstone Town Council, said: "Everyone’s shocked by these events. It’s stunned the community.
"We’re trying to pull together to listen to what people have to got to say and support the family and friends.
"It’s a close knit community."
Police said the man had been near the park's Bramble Way entrance at about 18:30 BST when he was seriously assaulted by a group of young people who left the scene before emergency services arrived.
Five children were detained following inquiries, the force said.
Due to prior police contact with the victim, the force will be making a voluntary referral to the Independent Office of Police Conduct (IOPC), it added.
Detectives have been speaking to residents in the area and have appealed for anyone who was in the park on Sunday evening to come forward.
Nearby residents expressed their shock at hearing the news.
Julie March, 38, said: “It’s tragic; we can’t even comprehend how it happened.
“And it’s just on our doorstep."
Emma Ghent, 34, said: “From what we have heard, he lives so close to us, so it is literally on our doorstep.
“He walks his dog every day in the park, and we have a dog; my husband walks the dog in the park.
“It could have been him; he could have been there at the same time.
“It’s just horrible.”
Det Insp Emma Matts said: "Sadly, following the death of the victim last night, this has now become a murder investigation.
“Officers are continuing to work at speed to establish the details of the attack and we have made a number of arrests as we continue to understand what has happened.
“A scene preservation will remain in place at the park while our investigation progresses. Local officers are also in the area carrying out reassurance patrols and can speak to anyone in the local community who has concerns.”
Officers have said they are particularly keen to speak to anyone who saw the victim before the assault or a group of young people leaving the area.