A boat
Refugees and immigrants on a boat they used detained at a Libyan Navy base in the coastal city of Tripoli in September, 2015Reuters

Up to 500 people may have died when a ship carrying refugees capsized between Libya and Italy on Saturday (April 20), the UN refugee agency said. The 41 survivors – 37 men, three women, and a three-year-old boy – were rescued by a merchant ship and taken to Kalamata, Greece.

If confirmed, the incident would be one of the worst tragedies of the Mediterranean refugee crisis in the last 12 months. On Tuesday (19 April), a team from the United Nations High Commissioner for Refugees (UNHCR) interviewed the survivors, who are from Somalia, Ethiopia, Egypt and Sudan.

"If confirmed, as many as 500 people may have lost their lives when a large ship went down in the Mediterranean Sea at an unknown location between Libya and Italy," said the agency.

"The survivors told us that they had been part of a group of between 100 and 200 people who departed last week from a locality near Tobruk in Libya on a 30-m [90ft] boat," said the UNHCR.

The agency said that after departing, the people smugglers tried to transfer some of the refugees to a larger ship "carrying hundreds of people in terribly overcrowded conditions," the UN agency said. However the larger vessel overturned during the transfer and sank.

The 41 survivors included those who had not transferred to the larger vessel, and those who had managed to swim back to the smaller vessel after the larger capsized. The survivors drifted at sea for three days before being rescued by the merchant vessel.

They are currently being housed by Greek authorities in a stadium in Kalamata.