The incident is said to have taken place at around 15:30 on Friday 4th November on Bennett Street, the road opposite Dover Park Primary School.
The man is said to have approached the boy, but the boy ran away towards Park Road. The man is then said to have left the area in the opposite direction towards St John’s Road.
Officers believe there were a lot of people around at this time. Anyone who witnessed a man acting suspiciously is asked to contact Police on 101, quoting 44160417508.
Hampshire Constabulary are reminding parents to remain vigilant, remind children of stranger danger and report anything or anyone suspicious to 101. In an emergency always call 999.