Police have recovered the bodies of a father near the rail track and his son from his home in Gazipur's Tongi.
The two bodies were recovered from the Bonomala area early on Sunday, said Tongi East Police Station chief Mehedi Hasan, reports bdnews24.com.
The dead were identified as Md Sohel Hossain, 52, a resident of the Bonomala area, and his younger son 18-year-old Sakib Hossain.
Sohan, 27, the eldest son of the deceased Sohel, has been taken into police custody for questioning.
Police recovered the bodies of the dead and sent them to the morgue at Gazipur Shaheed Tajuddin Ahmad Medical College Hospital.
Police and locals say that Sohel once lived in Singapore and Malaysia. A year ago, his wife died from an illness. Since then, he has lived with his two sons.
His younger son Sakib, a student of grade 11 in a private college, worked alongside his studies.
Late on Saturday night, Sakib's body was found in his home with his mouth gagged with pieces of cloth. His father Sohel's body was found lying on rail tracks in the Bonomala area.
Police say the elder son was sleeping in the next room at the time of the incident. He has a job in a private company. He told police that he was deep in slumber after finishing his night duty at work and did not notice anything.
Officer Mehedi said it is unclear whether this is a case of murder or suicide. "Police are conducting an investigation," he said.
"However, injury marks were found on the son's body and a blade was recovered next to it. It is suspected that the father committed suicide after killing his son."
Sohel's eldest son is being questioned over the incident and legal action is under way, the police officer said.
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