At least 45 refugees drowned in a shipwreck and more than 2,000 have been rescued from boats in the Mediterranean, the third major incident in as many days.
In the last week, around 14,000 people have been taken off flimsy vessels, the United Nations and Italian coastguard said.
Hundreds may have drowned, according to survivors and boat crews, though there are no official estimates of total casualties.
The Italian Navy ship Vega pulled around 135 people from a "half-submerged" rubber boat in one of 17 operations on Friday. The Vega recovered 45 bodies and is still searching for the missing people.
The warmer weather and calmer seas have led to a surge in the number of people trying to cross from Libya, the coastguard said.
Dozens of refugees are feared to have died when a boat sank off the Libyan coast on Thursday, when 4,000 were rescued in 22 separate operations.
A day before, at least five died when a wooden fishing boat carrying refugees capsized.
Photographs from the Italian Navy showed the blue fishing boat rocking precariously before capsizing and sending the refugees into the sea.
Refugees, many of whom do not know how to swim and do not have life jackets, pay hundreds or thousands of dollars to make the crossing from Libya to Italy.
In 2014 and 2015, more than 320,000 refugees arrived on Italian shores by boat and an estimated 7,000 died in the Mediterranean as they sought to reach Europe, according to the International Organisation for Migration.
The IOM said on Friday it estimates around 1,475 people have died in the Mediterranean this year.
Additional reporting by Reuters
