Dhaka Metropolitan Magistrate Mahmuda Akhter passed the order while dismissing his plea for bail on Saturday.
It came after Dhanmondi Police produced Firoz in court and sought 10 days' remand in each of the cases started by RAB.
Firoz, a member of Krishak League’s central committee and senior vice-president of manpower export association BAIRA, had tried to run for the Chandpur-5 seat in the last general election on the Awami League ticket.
The elite police unit said it seized foreign coins, playing cards and gambling equipment, casino-style scoreboard, a foreign-made firearm, three rounds of bullet and methamphetamine-based yaba tablets during the operation.
Asked why the four other arrestees were not named in the cases, Captain Ashik Billah of RAB-2 told bdnews24.com, "The four were paid staffers of Kalabagan Krira Chakra. It wouldn't have been prudent to charge them in the cases and there wasn't anything pointing to their involvement in the matter."
They were later released on bond.