Detective Constable Peter Russell, from Newport CID, said: “We believe both these attacks were carried out by the same group of men and happened within minutes of each other.
“We have already spoken to a number of people but are keen to hear from anyone who may have been in the area last night and saw or heard anything that can help us with our investigation.
“Incidents like this don’t happen often on the Isle of Wight but I’d like to remind people to be vigilant when out walking and be aware of their surroundings.”
Anyone with any information should contact Det Con Russell at Newport police station on 101 or the Crimestoppers on 0800 555 111.
Police believe that the three offenders may have been responsible for a similar attack shortly before the robbery.
Detectives have received a report of an assault in the same location, which is believed to involve the same group of men.
A 17-year-old boy was punched in the face but managed to run off.
Officers are conducting enquiries in the area and would like to speak to anyone who may know who was responsible.
Police on the Isle of Wight are investigating a robbery.
At around 11pm on Friday, a 26-year-old man was walking along Lugley Street in Newport when he became aware of three men behind him.
Without warning, one of the group punched him in the face knocking him to the ground.
The man continued to be assaulted but residents heard his shouts for help and the group ran off. The man then discovered his wallet had been taken.