Police would like to speak to them as part of an ongoing investigation.
It was reported that at around 1.30am this morning (Thursday 29 March), two men were assaulted by a group of people in the tunnel that leads from Gunwharf Quays to The Hard in Portsmouth.
One of the victims, a 31-year-old man, was knocked unconscious and was taken to QA Hospital.
The second victim, a 40-year-old man, was also assaulted by the group.
Officers would like to identify the three people pictured as they may have information to assist our enquiries. If you know who they are, then please call police on 101.
A 24-year-old man from Portsmouth has been arrested on suspicion of causing grievous bodily harm with intent, and remains in custody at this time.
A 21-year-old man from Portsmouth was also arrested in connection with this incident but has been released without charge.
Anyone with information is asked to contact police on 101, quoting 44180115912, or call the charity Crimestoppers anonymously on 0800 555 111.