A shipwreck on the Italian island of Lampedusa has reportedly killed 41 people, Italian media reports.
ANSA and RAI television quoted survivors as saying the ship had left the Tunisian city of Sfax for Italy.
Four survivors were rescued by a Maltese ship and taken to Lampedusa by the Italian coast guard and were reported to be in a state of shock, according to authorities.
The survivors, three men and a woman from Ivory Coast and Guinea, said there were 45 people on board, including three children.
Only 15 people were wearing life jackets, but they also drowned, survivors said.
The ship reportedly left last Thursday and traveled for about six hours before being overturned by a large wave.
According to Italian authorities, more than 90,000 people have reached Italian shores after crossing the Mediterranean Sea.
This represents an increase of more than double compared to the same period last year.
While many are caught off the coast of North Africa, most of those who make it through are picked up by the Italian coastguard or charity boats that take them to reception centres.
The Mediterranean crossing is one of the most dangerous migrant routes in the world.
According to the International Organization for Migration (IOM), almost 28,000 people have disappeared trying to cross the sea since 2014.