Officers are investigating a second alleged assault in two days - in the same bar.
Police are probing an incident that took place in the early hours of Sunday in the Walkabout bar in Carlisle.
An unknown suspect is alleged to have punched the victim to the face, causing bleeding from the lips.
The force is also investigating an incident that left a man with a fractured skull in Walkabout at 1.30am on Monday morning.
A suspect, who is a 31-year-old Carlisle man, was arrested and released under investigation.
Witnesses to the incident on Sunday morning should contact PC 2654 Hunter on 101.
Anyone with any information on the incident on Monday morning should contact DC 2328 Gibson on 101.
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