The tragedy late Wednesday off the Tunisian city of Zarzis came a day after a deadly airstrike on a Libyan detention center killed at least 44 migrants. Tunisian fishermen came across the sinking boat and were able to rescue four men, but could not find any of the other passengers, said Lorena Lando, head of the International Organization for Migration in Tunisia. One of the four, a man from Ivory Coast, died overnight and the other three remain hospitalized.

Earlier this week, another boat from Libya made it to the Tunisian port of Sfax with 65 people on board.