The Criminal Investigation Department (CID) arrested a man and his two associates more than a decade after killing his wife and two-month-old son.
The arrestees are Md Sohel Fakir, 37, and his associates Anwar Hossain and Liton Mia.
According to the case's first information report, Sohel married Ratna Begum, 20, a garments worker, in 2006 hiding his original address. They had a son named Md Nuruzzaman.
Later, Sohel married Kalpona Akhter, another garments worker, concealing information about his first marriage.
Kalpona's relatives started putting pressure on Sohel after learning about his first marriage, according to Special Super of CID, Dhaka Metro East Kanij Fatema said.
Sohel then planned to kill his wife and son. Sohel, along with Kalpana's uncle Liton and cousin Anwar, took Ratna and Nuruzzaman beside rail line between Mouchak and Mirjapur under Kaliakoir Police Station in Gazipur.
They strangulated Ratna to death and threw Nuruzzaman into a nearby pond.
Ratna' father Abdul Latif Molla filed a case at Dhaka Railway Police Station on July 27, 2007 accusing Sohel.
After investigation, the railway police submitted the final report. Police failed to collect permanent or temporary addresses of the accused Sohel.
As the state lawyer opposed the report, the Chief Judicial Magistrate, in January this year, ordered CID to investigate the case.
CID finally solved the case and arrested the trio, said Kanij Fatema.
Sohel was arrested on October 27 from Bhaluka upazila in Mymensingh while Liton and Anwar were arrested the following day from Kaliakoir in Gazipur.
Sohel, in his confessional statement before the Dhaka Chief Metropolitan Magistrate Court, said he killed his wife and two-year-old son with the help of Anwar and Liton, Kanij Fatema added.