The Italian coastguard began a search for survivors Saturday after a vessel carrying migrants capsized off the Mediterranean island of Lampedusa overnight.
Officials said in a statement that the craft had overturned as the coastguard was bringing migrants aboard its own boats off the island located between Sicily, Tunisia and Libya.
While around 40 people were saved, survivors of the accident said five were missing from the original number aboard.
The coastguard said a helicopter had been sent to search for any more still at sea.
Officials did not specify where the migrants had come from.
The overnight operation had followed "an especially intense day, as a large number of vessels carrying migrants was reported" on Friday, the coastguard said.
