Around 250 people are missing after a boat sank in the Andaman Sea last week, United Nations agencies have said.
The vessel left Bangladesh on 4 April bound for Malaysia.
It carried Rohingya refugees and Bangladeshi nationals, including children.
The boat went down because of strong winds, rough seas and overcrowding.
Rescuers found nine survivors on 9 April.
They clung to drums and wooden debris while they drifted in the open water.
A Bangladesh-flagged ship picked them up.
The United Nations refugee agency and the International Organisation for Migration issued a joint statement on the incident.
They noted that the passengers had set out on a dangerous sea crossing in search of better opportunities.
Many Rohingya people continue to make these journeys from camps in Bangladesh, where they face limited prospects after fleeing Myanmar.
Details of exactly when the boat sank remain unclear.
Search efforts continue, but hopes of finding more survivors have faded as time passes.
This event draws attention to the risks that thousands of people take each year on similar routes across the Indian Ocean.
Boats often leave from areas near Cox’s Bazar or Teknaf in Bangladesh.
Conditions at sea can change quickly, and vessels frequently carry far more passengers than they can safely hold.
UN officials have called for safer pathways and more support for displaced communities so that families do not feel they must risk their lives in this way.
For now, the focus stays on the families of those still unaccounted for.
