The boat overturned while trying to navigating rough seas en route to Bangladesh, the International Organization for Migration (IOM) said.
The agency said in a statement that the bodies of 15 people were recovered shortly after the incident, which happened on Thursday. Eight more bodies were retrieved from two locations on Friday morning. Two of the dead were women aged 35 and 49 as well as six children, the statement added.
An IOM field team was deployed to provide assistance to the 17 survivors pulled from the water on Thursday.
Of the 10 who required medical treatment at a hospital, six — four men and two children — have now been released. All will be accommodated at Kutupalong, a government-run refugee camp in southern Bangladesh.
One of the men released from hospital told IOM that he thought around 80 people, of which he estimated 50 children traveling without their parents, were onboard when the boat got into trouble.
The survivor said his 22-year-old wife, eight-year-old son and three-month-old twins had perished in the incident.
This eyewitness account led the migration agency to determine that the whereabouts of around 40 refugees are still unaccounted for.