Senior Judicial Magistrate Najmun Nahar instructed the OC of Nabinagar Police Station on Wednesday to lodge the case after hearing a petition by the victim's brother, Mehedi Hasan.
On Sunday, Hassan filed a petition before the court claiming his brother, businessman Shahnur Alam, was killed by RAB-14 personnel.
He alleged that RAB had detained and murdered Shahnur on April 29.
His body was found on May 6.
Hasan accused RAB-14's Bhairab camp commander Major AZM Sakib Siddiki and Sub Inspector (SI) Md Enamul Haque of the murder.
Other accused are nine unnamed RAB personnel and Nazrul Islam,58, and Abu Taher Mia,45, who hail from Krishnanagar of Nabinagar.
Recently, a murder case was also filed against RAB in Laksam upazila of Comilla for abducting two BNP leaders.
Earlier, three RAB officers had been arrested for murdering seven people in Narayanganj
These incidents have fuelled a public outcry against the RAB with many , including BNP chairperson Khaleda Zia, demanding the force should be disbanded -- but Prime Minister Sheikh Hasina has ruled that out.