Witnesses told police that a woman exposed her buttocks to two teenage girls in the bathroom of the Riverside Quay observation deck, in Melbourne around 8.30pm on Sunday.
The girls were on a school excursion.
The two girls left the bathroom to join their class when the woman walked past the group, and allegedly pulled her shirt down, exposing herself again.
The woman believed to be in her late 20s to early 30s, is described as having a medium build with blonde hair.
Police have released an image of the lady they allege indecently exposed herself to the teenagers.
She was seen leaving the observation deck with a man.
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