Police received reports of a person exposing themselves in the middle of a road.
Officers have arrested a 24-year-old from Portsmouth on suspicion of wilful obstruction of the highway and exposure under the sexual offences act.
They remain in police custody.
Anyone who witnessed the incident in Milton Road, Portsmouth is urged to call 101 quoting 44230102585.
The incident took place today (Tuesday 14) at 2.20pm.