Choppy waters are complicating the search for dozens of African migrants who are missing and believed dead after their boat sank off the Italian island of Lampedusa.
Authorities have recovered 111 bodies and expect to find many others in the wreckage of the ship, now sitting in about 40 meters of water.
Rescue teams saved 155 people after the boat, carrying an estimated 500 people, sank Thursday. The U.N. refugee agency says all but one of the survivors is Eritrean, with the other being Tunisian.
Italy is observing an official day or mourning for the dead migrants.
Pope Francis, on a visit to the Italian town of Assisi, proclaimed Friday "a day of tears." Flags are flying at half staff, and schools are observing a minute of silence for the victims.
The Italian state news agency ANSA said the boat, carrying Eritrean and Somali asylum seekers, went down in flames Thursday after migrants tried to send a distress signal by lighting a blanket on fire. Witnesses said the fire inadvertently ignited leaking fuel.
The disaster, described as one of Italy's worst migrant maritime tragedies, came days after 13 would-be migrants drowned off the coast of nearby Sicily after their boat sank and they tried to swim to shore.
Lampedusa, an island closer to continental Africa than to the Italian mainland, is often the destination for boats full of migrants seeking entrance to the European Union.
The United Nations refugee agency says the boat originated in Libya.
Speaking Friday, U.N. High Commissioner for Refugees Antonio Guterres called for a crackdown on human smugglers and greater protection for refugees.
The blog Fortress Europe, which tallies migrant deaths, says more than 6,000 asylum seekers, mostly from Africa, have died in the Sicilian Channel since 1994.