The woman, a mechanical engineer by profession, alleged in her complaint that the incident occurred last night at the mall located within Survey Park police station limits in the southern part of the city, police said today.
She noticed that a store employee was trying to take her pictures using a mobile phone through one of the holes on the wall of the ladies' trial room where she was trying out clothes, police said.
The police have started a probe on the basis of the woman's complaint.
"The lady's friend caught hold of the accused man who, managed to escape leaving the mobile phone behind which will prove to be a vital clue in our probe," the officer from Survey Police Station said adding that a search of the person has been initiated.
The shopping mall authorities, however, have said there was no camera inside the trial room.