The two others accused are former deputy commissioners (DCs) of police Md Moshiur Rahman and Md Jewel Rana.
Dhaka Metropolitan Magistrate GM Farhan Ishtiyak passed the orders as police produced the four accused before the court and pleaded to show them arrested in the cases, reports BSS.
Of the four, Majumder was shown arrested in two separate murder cases filed with the Mirpur Model Police Station, while Mamun was shown arrested in a murder case filed with the Hajaribagh Police Station.
Former DCs of Dhaka Metropolitan Police's (DMP) detective branch (DB) Md Moshiur Rahman and Md Jewel Rana were shown arrested in a murder case filed with the capital's Dhanmandi Police Station.