Four persons posing as crime branch sleuths from Chennai City Police took away 1 kg of gold from a goldsmith's shop on Vysial Street in the early hours of Thursday.
Police said that the shop owner V. Krishnamoorthy (34) of Thrissur left for his native place on Wednesday. His brother Dinesh Kumar (23) and five workers were at work on Wednesday night.
Four men knocked the door asking for Krishnamoorthy. They identified themselves as police personnel, entered the shop and threatened the workers at knife point. The workers were gagged and locked inside a room after relieving them of their cellular phones. They decamped with 1 kg of gold.