The brother of a registered medical practitioner and two of his accomplices have been arrested in Greater Kailash Part-I here for alleged involvement in several cases of robbing people after injecting them with sedatives.

The accused have been identified as Sompal alias Sonu (30), Amit Kumar (22) and Soh Singh (21). Sompal, who owns agricultural land in Uttar Pradesh, used to provide assistance to his brother, a medical practitioner, in his job and gained knowledge in the use of sedatives. Amit and Soh, both farmers, are also residents of UP.

The three would gain entry into houses posing as salesmen, tie up the family and make off with cash and jewellery after injecting them with sedatives, the police said.