There were 33 migrants alive on the boat, which was found in the Alboran Sea between Spain and Morocco on Thursday, according to the report.
The boat had departed from Morocco on Tuesday and was brought to the city of Almeria.
Another 12 people from the boat were still missing, media reported.
Spain overtook Italy as the most common point of entry for migrants trying to reach Europe illegally this year.
The International Organisation for Migration (IOM) estimated that more than 55,000 people used the West Mediterranean route to reach Europe this year.