A man sustained serious injuries after being set upon on licensed premises at Friary Road in Armagh at the weekend.
He was one of four members of staff assaulted during the incident, which happened shortly before 2am on Sunday.
It came about after a group of males had reportedly been asked to leave the premises.
The injured member of staff, aged in his 40s, was taken to hospital for treatment.
Those involved are understood to have fled the scene in a blue Volkswagen Golf.
Police have confirmed, however, that a 31-year-old man has been detailed for a number of alleged offences. He was arrested on suspicion of common assault, three charges of attempted GBH with intent, possessing an offensive weapon with intent to commit an indicatable offence and being disorderly on licensed premises.
The man has since been released on bail pending further enquiries.
Police in Armagh, meanwhile, are appealing for information from anyone who witnessed the incident. They can be contacted on the non-emergency number 101.