Rapid Action Battalion (Rab) has arrested four members of Islamist outfit Allah'r Dal in Rangpur and Nilphamari.
The arrestees are Abdul Mabud alias Shamim (19) of Babu Para, Ershad Hosen (18) of Khotkhotia in Rangpur, Ali Hosen alias Feku (20) of Chhoto Rouda, and Jamal Uddin (25) of Domar upazila in Nilphamari.
Rab seized some printed and hand written documents from them.
Sources said Rab arrested Abdul Mabud Shamim from his Babu Para's residence on Tuesday.
Shamim disclosed the names of his three accomplices during the interrogation. Later, Rab detained them from their houses.
A Rab official said the arrestees admitted that they are members of Allah'r Dal and were trained by Motin Mehedi, detained in Kurigram few months ago.