Gardaí are appealing for witnesses after a man was found unresponsive in the city shortly after midnight.
The injured man in his 20's was taken to Cork University Hospital where he remains in a serious condition.
The scene at Winthropp Street is currently preserved for a technical examination.
Anyone with any information about the incident or was in the area between midnight and 1am this morning is asked to contact Gardaí.
Gardaí told RedFM News, "Any persons who may have camera footage (including dash-cam) from the surrounding area of Winthrop Street and Patrick Street between midnight 12:00am and 1:00am is asked to make this footage available to Gardaí.
Anyone with any information is asked to contact Anglesea Street Garda Station on 021 452 2000, the Garda Confidential Line on 1800 666 111 or any Garda Station."
