Omar Faruque, 24, is posted at the District and Sessions Court.
He was handed over through a brief flag meeting between BSF and Border Guard Bangladesh (BGB) around 6:30am.
Nilphamari BGB 56 Battalion Captain Lt Col Abdullah Al Mamun received Omar Faruque from BSF.
He is now under the custody of Panchagarh Sadar police.
Police Super Mohammad Yusuf Ali on Monday night confirmed the matter.
Sadar police SI Md Jamal Hossain said he is now under police custody and undergoing treatment.
No official comment was received from police or BGB as to why the policeman was detained by BSF.
