Two men have been injured in a stabbing in Nottingham, police have said.
One man suffered a chest wound after being attacked in Forest Recreation Ground at about 18:00 BST on Friday, said Nottinghamshire Police.
He was taken to hospital, but his injuries were not life-threatening. A second man who tried to prevent the attack suffered a wound to his hand.
Det Con Michael Love said it was a "nasty assault that left two people requiring hospital treatment".
He added: "We are working to understand the circumstances that led up to this attack and would like to speak to anyone who may have witnessed the incident."