“Twenty-three people have been confirmed dead … 40 are missing and presumed drowned,” International Organization for Migration spokesman Joel Millman told reporters in Geneva, referring to the Thursday accident.
“The total fatality toll be in the range of 60,” he added, updating a previous toll of 19.
Survivors from the accident told IOM staff that the boat was carrying about 80 people, including 50 children, who were believed to be fleeing violence from Myanmar’s northern Rakhine state.
“Survivors described being at sea all night, having no food,” Millman said.
The drowning tragedy is the latest in a series of deadly accidents as desperate refugees surge into Bangladesh, where they are penned into ramshackle tent cities amid dire shortages of nearly all forms of aid.
Witnesses and survivors previously said that the overturned vessel was just metres from the coast in rough waters, after it was lashed by torrential rain and high winds.
“The Bay of Bengal has been a notorious killing zone for many years,” Millman added, highlighting the dangers facing Rohingya migrants seeking safety via the sea.
He added that the “captain” of the vessel, who is a suspected trafficker, is missing and presumed dead, but not included in IOM’s death toll, which counts only the migrants.
The UN Security Council voted to hold the body’s first public meeting on Myanmar since 2009, with UN chief Antonio Guterres termed the situation as a “nightmare”.
US envoy to the UN, Nikki Haley, said “We cannot be afraid to call the actions of the Burmese authorities what they appear to be: a brutal, sustained campaign to cleanse the country of an ethnic minority.
“And it should shame senior Burmese leaders who have sacrificed so much for an open, democratic Burma,” she added, in what appeared to be a rebuke to the country’s Nobel Peace Prize-winning leader Aung San Suu Kyi, whose reputation as a human rights champion has been left battered by the crisis.
Burma is an alternative name for Myanmar.
Myanmar’s national security adviser U Thaung Tun however insisted there was “No ethnic cleaning, no genocide in Myanmar”.
Myanmar has received backing from close ally China and Russia.