Images on Spanish media on Friday showed exhausted migrants lying on the pavement in Melilla, some with bloodied hands and torn clothes.
By Saturday, calm had returned to the border area, with Moroccan security forces lightly deployed and no migrants to be seen.
Mohamed Amine Abidar of the AMDH said migrants, who are often rounded up by authorities and taken to cities further south, had "probably moved away for fear of being displaced".