REUTERS/Handout
The United Nations Refugee Agency UNHCR said in a press release that about 500 Eritreans were on board the boat, which set sail from Libya.
Half a mile off the coast of the Italian island of Lampedusa, midway between North Africa and Sicily, the boat caught fire and sank, the agency said.
About 151 people were rescued.
UNHCR commended the action of the Italian coast guard, but UN High Commissioner for Refugees Antonio Guterres "expressed his dismay at a rising global phenomenon of migrants and people fleeing conflict or persecution and perishing at sea," according to the release.
Earlier this week, 13 men drowned near the southern coast of