In a statement, the coast guard quotes survivors as saying some 30 migrants were missing and it recovered the body of a boy and a woman from one of the capsized vessels.
Some 20 others were stranded Sunday on rocks after a third shipwreck.
According to those who were rescued from the shipwrecked vessels late Saturday, some 23 nautical miles (42.5 kilometers) southwest of Lampedusa, 28 people were missing from one and three from the other.
Meanwhile, 20 migrants were clinging desperately to jagged rocks of a tall reef off Lampedusa since early Saturday after a third boat crashed into the craggy outcropping west of the island’s lighthouse. Strong winds and powerful waves made any Coast Guard rescue too dangerous.
The coast guard office in Palermo requested the help of a Sicily-based Alpine and Cave Rescue group, which flew two experts aboard an Italian air force helicopter. The experts were planning to rescue the stranded migrants using the helicopter, the mountaineering group said.
Earlier, Italian helicopters dropped food and water down to the migrants, Italian state TV reported.
So many have made the crossing in smugglers’ unseaworthy boats launched from Libya and Tunisia in recent days that 2,450 migrants were currently housed at Lampedusa’s temporary residence, which has a capacity of about 400, said Ignazio Schintu, an official of the Italian Red Cross which runs the center. Once the winds slacken and the seas turn calm, Italy will resume ferrying hundreds of them to Sicily to ease the overcrowding, he told state TV.
The two boats that capsized in open seas were believed to have set out from Sfax — a Tunisian port — on Thursday, when sea conditions were good, according to authorities.
But since sea conditions were forecast to turn bad on Saturday, “it’s even more criminal for smugglers to let them leave,” said Flavio Di Giacomo, a spokesperson from the U.N. migration agency IOM.
Before Saturday, a total of 1,814 migrants were known to have perished while attempting the Mediterranean crossing to Italy in boats launched from Tunisia or Libya, he said.
Libyan departures used to be riskier, he said, but because lately Tunisia-based smugglers have been using particularly flimsy vessels, that route is becoming increasingly deadlier.
Migrants from sub-Saharan Africa are setting out from Tunisia in “fragile iron vessels that after 24 hours often break in two, and the migrants fall into the sea,” Di Giacomo said, in an audio message from Sicily.