According to a police statement, the gang threatened to kill the minors or traffic their organs if their relatives did not pay 5,000 dirhams (€460 or $520).
The gang was made up of six Morrocan nationals who were arrested mid-March. Four were later placed in provisional detention pending further investigation.
They would first help the minors travel to Spain illegally. They would then either kidnap them as soon as they arrived or go fetch them at child protection centres where they had been taken.
“They had the necessary contacts to take them out as quickly as possible,” police said.
More than 7,000 minors, accompanied or not by family members, emigrated to Spain in 2018, according to human rights NGO APDHA, or nearly double the number in 2017.
Most of unaccompanied minors are Morrocan.