More than 400 migrants were rescued in seven different operations over a 72-hour period from 9 May, according to a statement from the non-profit organization Doctors Without Borders.
Among those on board were 195 minors, including two under the age of one, said the NGO.
Rescuers from the rescue ship Geo Barents said many of those on board are victims of sexual and physical abuse, four of whom boarded boats to Europe with broken bones as a result of violence in Libya.