They were detained during several overnight raids on different places in Dhaka City on Thursday, RAB-1 commander Lt Col Tuhin Mohammad Masud said.
The elite force seized Tk 3.9 million which the detainees took from the youths after promising them jobs in the army, he said.
False appointment letters of the Cantonment Board were also seized.
Kashem and Nasim are retired members of the army while Hasan is a former policeman.
RAB official Masud said four persons, identified as ‘Rafikul’, ‘Tarikul’, ‘Didar’, and ‘Sabuj’, managed to escape.
Rafikul and Tarikul were sacked from the army while Didar was expelled from the BGB, Masud said quoting the detainees.
“This syndicate reportedly threatened those who found out that their appointment letters were forged to keep mum,” he added.