Officials said the incident was reported at about 4:00 PM when an on-duty CISF official detected suspicious movements of the trio at the airport terminal.
It was later detected that the three Delhi-based persons were allegedly conned by someone with a fake promise of providing them employment at the IGIA and they were subsequently handed over the fake airport entry passes.
It was found, they said, that the trio were duped of about Rs 1.10 lakh by the conman, who they said, met them at a metro station a few days ago.