K Madhu, S Janaiah Chary and J Mahesh allegedly posed as personnels of police's Special Operation Team (SOT).
Madhu had worked as a home guard before quitting the service. He and two others used to extort petty sums, from Rs 500 to Rs 1,000, from victims in the area under L B Nagar police station, a release from Cyberabad police said.
Acting on a tip-off, SOT officers nabbed the trio today. Home Guard I-cards were also seized from their possession.
Further probe is on.