The victims of the Narayanganj 5-murder died from head injuries, Dr Asaduzzaman who carried out the autopsy on the bodies has said.
A three-member board conducted the post-mortem at Narayanganj General (Victoria) Hospital on Sunday afternoon.
After the autopsies, Dr Asaduzzaman briefed reporters.
He said: "The killers tried to suffocate the victims but they died from head injuries."
Multiple injury marks were also visible on various parts of their bodies, he added.
Police on Saturday night recovered the bodies of five members of a family in a house in the Baburail area of Narayanganj sadar upazila. The dead are Taslima, 35, her daughter Sumaiya, 7, son Shanto, 10, brother Morshedul Islam, 20, and sister-in-law Lamia, 20.
Police say the murders were likely committed sometime between Friday night and Saturday morning.
Police have detained seven people for interrogation in this connection.