The survivors are Syrian citizens who told rescuers that three children are among the missing, the reports said.
The seven survivors were rescued by the coast guard and said they were travelling on a boat that had set off from Libya a few days ago, with 28 people on board.
Nicola Dell’Arciprete, UNICEF country co-ordinator for Italy, denounced “another tragic shipwreck off the coast of Lampedusa”.
“Most of the survivors claim to have lost family members. We are on the spot with our operational teams,” he wrote on X.
The central Mediterranean is one of the world’s deadliest migration routes.
According to the UN migration agency IOM, more than 2500 migrants died or went missing attempting the crossing last year, and 1047 this year, as of Tuesday.
The latest figures from the Italian interior ministry recorded that more than 43,000 migrants had reached Italy so far in 2024, well down on previous years.
AAP