The latest figures come amid criticism over the pace of migrant returns from the Spanish territory in North Africa, adding political pressure on Socialist Prime Minister Pedro Sanchez ahead of next year’s election.

More than 70,000 migrants entered Ceuta on July 30 and 31 in an unprecedented and deadly rush, with most returning to Morocco in the following hours.

The government has had to identify the thousands of migrants who have remained for weeks to check if they are entitled to asylum, while unaccompanied children cannot be summarily deported.

Angel Victor Torres, the minister tasked with leading the government's response, said in a video posted to social media that 5,321 people had "voluntarily returned" to Morocco since August 10.

Ninety people had "given up" their request for international protection and "almost 1,000 people are being registered with the aim of being able to complete their return proceedings", Torres added.

The minister did not say how many migrants remained in Ceuta after those returns, a figure that has consistently sparked controversy between the leftist government and the conservative-run city.

On Friday, Ceuta's leader Juan Jesus Vivas, of the main opposition right-wing Popular Party, put their number at 13,000, but the government's estimations have been significantly lower.

Locals have protested regularly as the migrants continue to camp on beaches and sleep in the streets, accusing the government of abandoning the overwhelmed city amid a humanitarian crisis.

The migration ministry announced on Sunday the creation of another 864 places in temporary migrant shelters, taking the total to around 4,300 and with a view to reaching 6,000 "in the near future".

Doubts about what the government knew beforehand and the possible role of Morocco, with which Madrid has spent years trying to improve relations, have also increased the political fallout for Sanchez.