More than 700 sub-Saharan migrants on Thursday stormed the border fence surrounding the Spanish enclave of Ceuta in Morocco, with dozens injured in an incursion of “unprecedented violence”.

Sixteen migrants and ten officers from Spain’s Guardia Civil received hospital treatment following Thursday morning’s incident, during which the group bombarded agents with quicklime, sticks, stones and bags of excrement as well as aerosols used as flame throwers, the force said in a statement.

The incursion, which comes days after Spain officially overtook Italy in migrant arrivals by sea, occurred at around 6.30 am when the men used angle grinders and shears to cut through the outer and inner layers of the border fence.

The group also bore defensive equipment such as home-made shields and body armour, the Guardia Civil said, and once through the fence continued to attack agents and security vehicles. The force later recovered “Molotov cocktails and bags of hashish”, it added.

The group scrambled over the razor wire fences “all of a sudden, with much violence”, a Guardia Civil spokesperson in Ceuta said.