She received the shock of her life when the lift doors opened on the second floor - standing in front of her, completely naked, was a man in his 20s.
With his arms straddling either side of the lift’s entrance, he stared intently at the 12-year-old, blocking her escape path. He then entered the lift.
"The pervert grabbed her bag, and also touched her hand," said the girl's uncle.
He eventually fled when the girl started crying and shouting for help.
The police has since arrested a suspect.