Islanders firstly thought there was a blaze in the store around 08:00 due to smoke appearing to emanate from the building.
It’s believed that the intruder alarm, which activated the smoke screen, was accidentally set off when the town cosmetics store was opened this morning.
Broad Street, Pitt Street, Dumaresq Street and part of King Street were all closed off as firefighters went to inspect the source of the ‘fire’.
Pedestrians were asked on social media by police to “avoid the area”.
The area was opened up again around an hour later by 09:00.