Four members of a family, including two children, were found dead with their throats slit at village Bahadurpur of Niamatpur upazila in Naogaon on early Tuesday.
The deceased were identified as Habibur Rahman, 32, his wife Popy Sultana, 25, their son Parvez, 9, and three-year-old daughter Sadiya Akter.
According to local people and police, Habibur Rahman went to sleep with his family after dinner on Monday night.
On Tuesday morning, a neighbour noticed that the door of their house was open and found the bodies inside with their throats slit.
Her screams alerted villagers who then informed the police.
Police reached the scene at about 9:00am and recovered the bodies.
Local people said that the killings might have been linked to a long-standing land dispute although police have not confirmed the motive.
Niamatpur Police Station officer-in-charge Mahbubur Rahman said that the bodies would be sent to Naogaon 250-bed General Hospital for post-mortem examinations.
He said that the incident was being investigated with the highest priority and legal action was underway.