The Italian coast guard said it received a cooperation request from the Maltese search and rescue (SAR) authority after the boat capsized approximately 30 miles (50 km) southeast of the island of Lampedusa on Wednesday.
The coast guard said it dispatched its own patrol boat to the scene, which "rescued 22 survivors and recovered 9 deceased individuals, including a baby."
The rescue operations "were particularly challenging due to adverse weather and sea conditions in the area with waves up to 2.50 metres," the coast guard said.
The nationality of the boat's passengers was not known but Lampedusa, which sits in the Mediterranean between Tunisia, Malta and the larger Italian island of Sicily, is the first port of call for many migrants seeking to reach the European Union.
"New terrible shipwreck near Lampedusa during a rescue operation," UNHCR Communication Officer Filippo Ungaro posted on X late on Wednesday. The survivors, taken to Lampedusa, were "in a state of hypothermia and shock," he added.
An aircraft from the Italian coast guard was conducting aerial searches for the missing in the area of the shipwreck. In a separate operation, the Italian coast guard said it rescued 37 migrants "who were at the mercy of the waves aboard a small wooden boat about 7 meters long" off the coast of Lampedusa on Wednesday.