NEW DELHI, January 8: With the arrest of three men, the Crime Branch has claimed to have busted a gang of interstate imposters. The gang is allegedly led by Mumbai-resident Hanif, and the men would pose as CBI officers and dupe businessmen.According to the police, the men would call their victims ``doctor'' and other gang members ``karoo''. They would strike in markets before the shops opened. The men would chat with these people about how they would send goods to other markets, and then the ``karoo'' would lift his collar and signal to the other gang members.After this the gang leader would introduce himself as a CBI official on special checking duty claiming that there has just been a minor bomb blast in the city. The ``CBI official'' would then check the ``karoo'' who would show the cash he was carrying with him. The ``official'' would then ask both the ``karoo'' and the doctor'' to accompany him to the CBI headquarters.At this time the third gangmember would arrive in an autorickshaw, in which the three would sit. The ``karoo'' would quickly exchange the victim's packet with a wad of paper. After this the gang leader would ask the ``karoo'' to be taken to the police station for verification and tell the victim to get down from the autorickshaw. The victim would be given a letter stating that he had been properly searched by the CBI.