Morocco's interior ministry on Sunday issued its first toll for those who died trying to reach Spain's North African enclave of Ceuta last week, saying 11 people had died.

The figures are significantly lower than those issued by Spain, which says at least 72 people died.

Tens of thousands of would-be migrants crossed into the territory between Wednesday and Friday, sparking a diplomatic row within the European Union as some member states criticised Spain's migration policies.

Rachid El Khalfi, a spokesman for Morocco's interior ministry, said that of the 11 who died, 10 had drowned, while an eleventh person fell from a rocky area.

Morocco was working with Spain to check the toll figures and to identify bodies found on Spanish territory.

The ministry blamed the sudden surge on the "malicious exploitation" of social media and the "spread of misleading information".

But it also cited the "misinterpretations of legal provisions" -- a reference to a July 8 Spanish Supreme Court ruling that migrants arriving by sea should not be returned as quickly as others.

The ministry said there had been 40,000 attempts to cross into Ceuta illegally.

Another 1,135 people had tried to illegally enter the Spanish territory of Melilla, further east, but had been immediately returned to Moroccan territory, the ministry added.

Spain says more than 60,000 managed to enter Ceuta in recent days although most have now returned to Morocco.

The Moroccan Association for Human Rights (AMDH) has said there were "nearly 130 victims" with dozens more missing.

Prosecutors have opened an official investigation into what happened, said the ministry.