Sylhet municipal workers were seen dumping market waste into the river, a resident says
The national professor and historian, who was awarded the Ekushey Padak and the Swadhinata Dibash (independence) Award, died around 6am at his Banani residence in Dhaka.
Family members said he was suffering from old-age complications.
President Md Abdul Hamid and Prime Minister Sheikh Hasina have expressed their condolences over the death of the pre-eminent historian.
The body will be kept at the Central Shaheed Minar from 2:30pm to 4pm to enable mourners to pay their last respects. The funeral prayers will be held at the Dhaka University mosque after the Asr prayers before his burial at the Banani graveyard.