According to the survivors, about 240 migrants left the Libyan port city of Tobruk heading for Italy. Once out in the Mediterranean, they were transferred to a larger boat already packed with more than 300 people, which then capsized.
Italy´s President, Sergio Mattarella, said Europe needed to reflect in the face of "yet another tragedy in the Mediterranean in which, it seems, several hundred people have died". His comments followed a report by BBC Arabic quoting the Somali ambassador to Europe that 400 people had died crossing from Egypt to Europe.
Reports said the refugees were fleeing to Italy from Somalia, Ethiopia and Eritrea in four boats which were ill-equipped for the journey.
Numbers of migrants from Libya to Italy have surged this year
In a separate incident, on Monday morning, the Italian coastguard said 108 refugees had been saved and six bodies recovered from a semi-submerged rubber dinghy on Sunday. Separately, 33 refugees were rescued overnight off eastern coast of Sicily.
The number of migrants arriving in Italy from Libya has surged recently - about 6,000 made the journey alone over a three-day period last week, the International Organization for Migration said
About 180,000 people have attempted to reach Europe by sea this year, with nearly 800 lives lost, the UN says.
A year ago, a fishing boat crowded with refugees sank in the Mediterranean with around 800 people trapped inside.
EU policymakers have been criticized of "killing by neglect" after they cut rescue missions in the Mediterranean.
The scaling back of search and rescue operations "created the conditions that led to massive loss of life," according to a report.
Tanya Steele, CEO of Save the Children, said: “The lack of concrete measures to protect children who gamble and lose their lives to reach the perceived safety of Europe should weigh on all our minds. A year on from one of the greatest migration tragedies in the Mediterranean, safe and legal routes have not been properly implemented.
Europe continues to see this migration crisis as primarily about safeguarding its own borders. A third of those desperate enough to make this perilous journey are children. Even though the European Commission has identified children as one of the most vulnerable groups, recommending relocation measures as a priority, in effect, this is only happening on paper”.