The Spanish enclave of Ceuta regained a measure of calm after a mass crossing of thousands of Moroccans that left at least 67 people dead, as arrivals from Morocco slowed to sporadic attempts, El País reported on August 1.

The crisis has exposed Spain to a fresh confrontation over migration policy and its management of the North African enclaves, straining relations with Rabat and igniting a domestic political row weeks after a Supreme Court ruling curbed summary returns.

Up to 60,000 Moroccans reached the enclave over several days, the highest numbers on record, with the peak on July 30 however the majority have been returned in recent hours, according to police authorities.

Migrants have been returning by the same route since July 31 they added, and Moroccan agents completed a closure of the border in the afternoon. Spanish security forces deployed a pneumatic barrier about 500 metres long beside the Tarajal border breakwater to slow further arrivals.

The mass entry left the city on edge, with the army deployed and the Civil Guard organising the flows. Shops, bars and petrol stations that had shut began to reopen cautiously.

Prime Minister Pedro Sánchez's government blamed the crisis in part on a Supreme Court ruling three weeks ago that barred summary returns of migrants intercepted at sea while trying to swim to the enclaves, and on trafficking networks.

Interior Minister Fernando Grande-Marlaska praised cooperation from Rabat, said Morocco was not a threat and said the government had reversed the situation within 24 hours.

Civil Guard maritime officers and divers worked to recover bodies off the Tarajal border, where the death toll continued to rise through the day.

"There are more dead in the sea," a police source said.

Humanitarian organisations warned that extending the barrier out to sea would force those attempting to swim across further into open water, raising the risk of more deaths.

Videos released from July 31 show dozens of men being ushered out in dumper trucks heading towards the Spanish border, leading several to suspect that the mass movement of people was deliberate and organised. Morocco claimed that "criminal gangs" organised the mass movement.