The deceased was identified as Md Musa, 55, son of Saleh Ahmed member, a resident of Meghal union of the upazila, said police sources.
Police arrested Md Saiful Islam Sarek, 17, an HSC student, in this connection, said Assistant Superintendent of Police (ASP) Md Latfur Rahman of Hathazari Circle.
“The incident took place at the Saleh Ahmed member house at Meghal union”, said the ASP.
Quoting family members, the ASP said Sarek hacked his father with a sharp weapon when he was coming out from a toilet around 8:30am leaving him critically injured.
“Family members rushed Musa to Chittagong Medical College Hospital (CMCH) where on-duty doctor declared him dead around 10:30am”, said the ASP.
Later, police arrested the boy and recovered the sharp weapon, said the ASP.
“Family members told police that the boy is mentally challenged for last one year, but, police did find any abnormal sign in his behavior during primary investigation”, said the ASP Lutfur.
The body was sent to the CMCH morgue for a post mortem examination. A case was filed.