Rangpur, Aug. 24 -- All four members of the family who were found dead in Rangpur city on Saturday were strangled to death while the disfigurement of their faces was caused by decomposition rather than any chemical substance, said Babul Kumar Biswas, the doctor who conducted their autopsies on Monday.

Babul Kumar, an assistant professor at the forensic medicine department of Rangpur Medical College Hospital, said there were no signs of chemical burns on the bodies.

"When a body decomposes, exposed areas outside the clothing can sometimes turn dark. This is part of the decomposition process," he told UNB over the phone in the afternoon.

He said the dark appearance of the victims' faces was caused by changes in blood and body tissues dur...