A boat carrying migrants ran into trouble on Monday off the coast of Nador, in the northeast of the kingdom, local authorities told AFP.
“Thirty-two sub-Saharan Africans were saved and the bodies of 11 migrants were recovered,” the same source said, without giving further details.
The death toll was put at 34 dead by organisations that aid migrants.
Spanish rights activist Helena Maleno tweeted: “34 dead, among them a baby, when a makeshift boat with 60 people on board sank… off Morocco”.
Morocco has seen an influx of migrants trying to reach Europe, most of them on boats bound for Spain or via the Spanish enclaves of Ceuta and Melilla in North Africa.
More than 40,000 migrants have reached Spain since the start of the year, including around 35,000 by the sea, according to the International Organization for Migration.