A 63-year-old man suffered a blow to the head with a walking stick after getting into a row with two pensioners walking their dog in a Lincoln park.
The man was walking his dog in Hartsholme Park in Lincoln between 9.20am and 10am when he encountered a man and a woman walking a tan-coloured Border Terrier.
The three got into an argument and the man was hit on the head with a walking stick, causing a cut.
The man and woman involved are described as being aged in their 70s, both of large build, and wearing green and blue jackets.
Anyone who witnessed the incident, or has any information that might be relevant to the enquiry, is asked to contact Lincolnshire Police on 101 quoting incident 115 of March 17.