The local administration has formed a five-member probe body over Thursday's trawler capsize in Bhola.
Bhola Deputy Commissioner Md Selim Reza said the probe committee would be headed by Additional District Magistrate Md Monwar Hossain.
“The committee has been asked to submit its report by Sunday,” he said.
The trawler, which was travelling from Kalatali to Manpura Sadar, sank after its hull developed cracks due to strong currents in the river, leaving six people dead.
Authorities on Friday began a fresh rescue operation as four people remained unaccounted for till the evening.
Of them, two hail from Bhola Sadar and the other two from Manpura, said Abu Hanif Shikder, officer-in-charge of Manpura police station.
Lieutenant Commander Mojahidur Rahman of the Coast Guard (south zone) said rescuers searched for the survivors in the river but to no avail.
The bodies of six victims, including four children, were handed over to their families on Thursday night. They all hailed from Manpura.
The local administration gave each of the six families Tk20,000, said Ershad Ali, upazila nirbahi officer of Manpura.
It was the third such accident in Manpura in the past one month.