Coast Guard Commander Filippo Marini said 43 bodies were recovered from within the ship's hold, while one was spotted by a helicopter floating near the wreck, before the operation was suspended for darkness.
Just 155 migrants, most if not all from Eritrea, survived Thursday's shipwreck. Survivors said there were some 500 would-be asylum seekers aboard when the ship capsized and sank in sight of land.
A disproportionate number of the dead are women: So far the bodies of 81 women have been recovered, while only six of the survivors were female. Eight of the dead are children.
"Inside, we're finding more women than men," Gianni Dessi, the coast guard official coordinating the diving operation, told Sky TG24. "We hope not, but we expect to find more children."
He said the scene inside the ship's hold is tough for divers, but that "maintaining cold blood is a quality that helps the operation."
The survivors were helping with the identification of the bodies, mostly through photographs. In some cases, divers also have recovered documents.
Thursday's shipwreck has one of the highest verified death tolls among migrant ship disasters in the Mediterranean Sea. Humanitarian organizations have had reports of large numbers of migrants being lost at sea, including one boat with 300 that disappeared in 2011, but the bodies in such cases are never recovered.
Also Tuesday, prosecutors in Agrigento, Sicily, said they had detained a 35-year-old Tunisian man who is believed to have been the captain of the ship. The suspect faces charges of aiding illegal immigration and multiple counts of homicide.
Tens of thousands of migrants from Africa and the Middle East try to cross the Mediterranean Sea each year, seeking a better life in Europe. Hundreds die in the process.
Take ABC13 with you!
Download our free apps for iPhone, iPad, and Android devices