Police officers found a man who had collapsed on the pavement in Northamptonshire.
Officers found him lying on the ground in Montagu Street in Kettering following an alleged assault.
The assault is believed to have happened during an incident in Bostons Diner sometime between 1.50am and 2am on Sunday, March 8.
The man was taken to Kettering General Hospital for treatment. A second man is also believed to have been injured in the same incident.
Witnesses, or anyone with information, are asked to call Northamptonshire Police on 101.
Alternatively, they can call the independent charity Crimestoppers anonymously on 0800 555 111 or use the anonymous online form at www.crimestoppers-uk.org.