They were each arrested at different intervals following the incident believed to have occurred within the Harbour Lights at around 16:00 on Friday 16 December.
One man was taken to hospital as a result of the incident. It is not known if he was one of the four arrested or a fifth man.
A police spokesperson said: “Enquiries into this matter are continuing, and officers would still like to speak to anyone who witnessed the incident who has not yet given a statement.
“You can speak to the investigating officers either by attending the police station or by calling 01481 222222.”
A number of videos of the incident have been circulating on social media and via WhatsApp – police have previously asked that this material is not shared any further.
Pictured: The above statement was shared by Guernsey Police on Friday night as they dealt with the incident in the immediate aftermath.
The Harbour Lights incident and a second alleged fight elsewhere in town on Friday night occurred just before and during what Guernsey Police call #tweetonthebeat .
It’s an exercise they have previously carried out where officers use Twitter to explain what they do during a shift.
Friday night saw officers attend incidents including a broken window, alleged harassment, and a domestic incident while Guernsey Police officers also conducted drink driving checks, and patrolled St Peter Port.
Pictured: Guernsey Police outside the Harbour Lights on Friday afternoon.