A woman struggled with two teenage robbers to retrieve her friend's necklace.
The women, aged 53 and 63, were attacked in Lily Marriott Park, in Barnes Heath Road, Crown Hills, Leicester, on Saturday evening.
Two youths, who are thought to be 15 or 16, snatched the necklace from one of the women as she walked past them.
One of the teenagers pushed the woman to the ground. Her friend however confronted the youth who was holding the necklace and fought to get it back.
Both men fled empty handed toward nearby Oxon Way.
The victim was taken to Leicester Royal Infirmary where she received treatment for face and shoulder injuries. She has since been discharged.
The women told police they believe the two attackers had been among a group which had earlier followed them through the park.
Detective Constable Amanda Thwaites said: "What should have been a pleasant walk in the sunshine ended in a shocking experience for these two ladies.
"One was left with substantial injuries and her friend who showed great bravery was left very shaken by the incident.
"We are appealing for witnesses who may have been walking in the park and saw two men matching these descriptions or witnessed the incident to contact us.
"We are particularly interested to speak to a man who contacted the victim's family to say that he witnessed the incident.
"He may have valuable information that could help us with our investigation."
The first suspect is white, aged 15 or 16, approximately 6ft and of slim build. He was wearing a black cardigan, a cream coloured T-shirt and cream coloured trousers.
The second youth is black, aged 15 or 16, 5ft 5ins to 5ft 6ins and of thin build. He has tightly curled, black shoulder-length hair and was wearing black clothing.
Anyone with information should contact Det Con Thwaites on 101, or Crimestoppers, which is anonymous, on 0800 555 111.
