At 12:58pm on Monday (23/11), the victim, a 50-year-old man, was found with head injuries near to the junction of Oak Tree Drive and Oakwood Lane, Gipton.
He was taken to hospital by ambulance and is continuing to receive treatment for injuries that are serious but are not believed to be life-threatening.
A scene was put in place to undergo forensic examination and was removed late last night.
Enquiries are ongoing to establish the circumstances
Detective Inspector Kevin Daly, of Leeds District CID, said: “We are carrying out extensive enquiries to establish the full circumstances of this incident. Initial indications are that the victim has been assaulted in the street by lone male suspect.
“We would like to hear from anyone who witnessed the incident or who saw anything suspicious in the area around this time which could assist the investigation, particularly anyone nearby with relevant CCTV or dashcam footage.”
Anyone with information is asked to contact Leeds District CID via 101 quoting crime reference 1320586747