"There are no more bodies inside the wreckage. The search will continue in areas outside the wreckage," a coast guard official said.
Divers from Italy's coast guard, border guard, military police, navy and fire brigade have all taken part in the nightmarish underwater operation at a depth of around 50 metres (164 feet).
The search will continue around the wreckage using underwater robotic devices, as well as from the air, the coast guard official said.
Only 155 survivors were rescued and an estimated 500 people -- most of them Eritreans and Somalis -- were on the boat which departed from Libya.