Moroccan authorities have intercepted dozens of migrants seeking to cross into the Spanish North African exclave of Ceuta, reports say.

More than 100 people were blocked trying to make their way to the border on the outskirts of the town of Fnideq, according to Moroccan security sources cited by Spanish media and the Reuters news agency.

It comes a fortnight after roughly 78,000 migrants arrived in the exclave by sea in a matter of hours - 100 of whom died, according to the city's mayor, who also said the vast majority of arrivals had returned to Morocco.

Security had been stepped up in the area after the influx and amid suggestions on social media of a second mass crossing attempt this weekend.

The security sources said 111 people had been detained in or around Fnideq - known in Spanish as Castillejos - about 3km (1.8 miles) from the border, the majority of whom were from sub-Saharan Africa.

Moroccan police - including some in riot gear - reportedly used tear gas to disperse groups of migrants gathered on nearby hills.

Earlier this week, Morocco's government said it was monitoring "the circulation of social media posts and messages of unknown origin" calling for a mass crossing on Saturday, and warned that it would prosecute organisers and participants.

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Security at the breakwater entrance was "10 times stronger than the previous day", Spanish newspaper El País reported.

Morocco had dispatched army officers, navy speedboats and drones to the border on Saturday, it said.

Madrid meanwhile deployed more than 1,500 security officers to patrol the area.

Spain has also installed a metal fence and a floating barrier following last month's influx.

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The crisis had calmed since breaking out in late July, but it has sparked tensions between EU nations which share open borders as well as criticism of the Spanish government.

Italy suspended the 29-member Schengen arrangement of free movement with Spain and introduced border checks on arrivals from Spain.

Italy was backed by Finland and Denmark, while the Czech Republic called for Spain's membership to be temporarily suspended.

Spain reacted angrily, with Prime Minister Pedro Sánchez noting Ceuta was not part of the Schengen area - and the migrants, therefore, had not arrived on the Spanish mainland and could travel to any other European country.

It urged Italy to drop its border controls - and introduced its own when Rome refused, citing the possibility of a new influx on 15 August.

On Saturday, Italy's Foreign Minister Antonio Tajani said his country had been afraid of a "risk of a new wave of arrivals in Ceuta".

"We're not waging any kind of 'battle' against Spain; we're simply carefully controlling arrivals," he said.

"Instead of worrying about us, Spain should worry about Morocco: that's where the problems are coming from, certainly not from our controls."