At least 69 people died, including 25 Malian nationals, after a boat headed from West Africa to Spain capsized off Morocco on December 19, Malian authorities said.
The makeshift boat was carrying around 80 people when it capsized.
Only 11 survived, the ministry of Malians abroad said in a statement on Thursday, after collecting information to reconstruct the incident.
A crisis unit has been set up to monitor the situation and will report any further updates, it added.
The Atlantic migration route from the coast of West Africa to the Canary Islands, typically used by African migrants trying to reach Spain, has seen a surge this year.
Years of conflict in the Sahel region that includes Mali, unemployment and the impact of climate change on farming communities are among the reasons why people attempt the crossing.
The route, which traces the Atlantic coasts of Mauritania and Morocco up to Spain, is one of the world’s deadliest.
An unprecedented nearly 5,000 migrants died at sea in the first five months of 2024 trying to reach the Spanish archipelago, migration rights group Walking Borders said in June.
