Teknaf Senior Judicial Magistrate Court Judge Tamanna Farah passed the order after hearing separate remand petitions filed by Rapid Action Battalion (RAB).
Those remanded are sub-Inspector Litan Miah and constables Safanur Karim, Kamal Hossain and Abdullah Al Mamun , Nurul Amin, Nizam Uddin and Mohamamd Ayas.
Earlier on Monday, a court sent the four policemen to jail in the murder case.
Later, they were placed on a 2-day remand
RAB on Tuesday detained three more suspects, who were made witnesses in the murder case filed by police.
Members of Rapid Action Battalion (RAB) arrested them from Marisbunia in Teknaf upazila of Cox’s Bazar district in connection with the killing of Major (retd) Sinha.
Major (retd) Sinha was killed in police firing at Baharchhara police check-post on July 31.
Sharmin Shahriar Ferdous, elder sister of Sinha, filed a case with Teknaf Senior Judicial Magistrate Court after the incident on August 5.
Senior Judicial Magistrate Tamanna Farah issued arrest warrants against all of the accused after taking the case into cognizance on that day.
OC Pradeep surrendered on the following day and later police took him to Cox’s Bazar.
The Home Ministry formed a four-member committee, headed by Mizanur Rahman, additional divisional commissioner (development), on August 2.