Authorities told the state news agency that at least 200 migrants tried to swim to the enclave, which is on a peninsula jutting out from the Moroccan shore. Some 150 were stopped while 13 others were sent to a local hospital.
With two Spanish enclaves on its coast, Morocco is a magnet for immigrants from all over Africa seeking jobs in Europe.
Every month, hundreds of immigrants attempt to force their way into Ceuta, near the city of Tetouan, and Melilla to the east.
Morocco has an estimated 25,000 illegal immigrants on its soil and has announced a new policy to regularize their status. AP