Some of the detainees were identified as Mohammad Sohag, 32, Sumi, 29, Mintu Mia, 38, Tuhin, 33, and Mabia, 25.
BGB sources said all of them are Bangladesh nationals.
A case was filed against them under Section 11 (1) (c) of the Passport Ordinance, 1973 at Maheshpur police station for entering Bangladesh illegally from India without a passport.