An alleyway running down the side of a terraced house on Avenue Road was cordoned off by Police for around 12 hours as scenes of crime investigators examined the area for evidence.
Officers were called to the scene in the early hours of the morning, shortly after 03:00.
A 33-year-old woman is the victim of the alleged sexual assault.
UPDATE MONDAY – The unnamed 39-year-old male from the Isle of Wight has been bailed until next month pending further enquiries.
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