Police are appealing for witnesses after three incidents outside Colours Nightclub in Douglas.
A woman needed hospital treatment for a facial injury after an incident involving three women outside the club at 3.20am on Sunday.
Shortly afterwards, another incident involving two men and two women led to a man sustaining a facial injury and also receiving hospital treatment.
As a result of both incidents, a 27 year-old woman and a 38 year-old man were arrested and are now on bail pending enquiries.
Police are also appealing for witnesses after a woman was assaulted in Colours in the early hours of Monday morning, between 2.40am and 3am.
They say she was assaulted by a woman in her late teens or early 20s in what appears to be an unprovoked attack.
A woman has been arrested and questioned and enquiries are on-going.
Anyone with information is asked to contact police headquarters on 631212.