Two women were killed in a stabbing at a residence in the Kathalbagan area of Kalabagan on Sunday morning.
Police identified them as Farzana Begum, also known as Ratri, 20, and her mother Firoza Begum, 38.
Kalabagan police said the incident occurred at about 9:30am.
Police said their preliminary inquiry indicates that an argument between Farzana and her husband, Hriday alias Shipon, preceded the incident.
Police alleged that Firoza intervened in an effort to stop the argument before both women were attacked with a sharp weapon.
Farzana died at the residence, police said.
Firoza was taken to Dhaka Medical College Hospital, where doctors declared her dead, police said.
Police said Hriday was taken into their custody after the incident, though one account described this as detention for questioning and another as an arrest.
Farzana’s father, Md Faruk Hossain, said the couple had been in conflict for several days and that he was outside the home at the time.
A police official at Dhaka Medical College Hospital said Firoza’s body was kept at the morgue and that post-mortem examinations were being prepared.
Police said they are investigating the specific circumstances and motive, and legal procedures are under way.