The theft took place yesterday when the shop owner and workers had gone out for lunch, they said.
The robbers allegedly broke into the shop --Rajratna Jewellers-- after drilling an opening in one of the walls on the mezzanine floor and fled away with the booty.
According to the complaint filed by owner Bharat Jain, the shop is situated in the busy locality just near the station in Kasturi Plaza area which is crowded with people.
Police suspect that the robbery is the handiwork of insiders who know the details of the shop.