The Crime Investigation Department (CID) of police filed a chargesheet against Raihanul Islam in a case filed in the case of stabbing and killing fish trader Shahinul Islam and three members of his family in Kalaroa, Satkhira.
Shafiqul Islam, the investigating officer of the case, filed the chargesheet in the court of Judge Bilas Kumar Mandal in Satkhira on Tuesday afternoon.
Satkhira CID inspector Shafiqul Islam said, "A charge sheet was filed against Raihanul Islam as the sole accused based on the testimony of 28 witnesses and a review of Raihanul Islam's statement under section 164 in the court."
Four family members including fish trader Shahinul Islam were killed in Khalshi village of Kalaroa upazila on 15 October.
Raihanul Islam, younger brother of the deceased, was detained for questioning on the day of the murder. The next day, Raihanul was arrested and sent to jail.
He later testified in the court that he had committed the murder.