Police have not specified what is alleged to have happened, saying only that it took place between 05:30 and 06:30 on Tuesday this week.
Officers are trying to get in contact with a woman who was waiting at the Halfway bus stop at the time and is believed to have witnessed part of what happened.
Anyone with information or who witnessed the incident is asked to call PC 138 Falla on 725111 or contact CrimeStoppers anonymously on 0800 555 111.