Migrants stage rooftop protest at Spain detention centre

Migrants protest on the roof of a detention centre in Madrid on October 19, 2016 (AFP Photo/Javier Soriano) (AFP)

Madrid (AFP) - Dozens of migrants rioted at a detention centre in Madrid, police said Wednesday, climbing onto the roof of the building where they spent the night and unfurling a banner reading "freedom".

By mid-morning on Wednesday they had voluntarily come down from the top of the centre, police said.

The "mutiny" kicked off late Tuesday at the centre in Madrid's southern district of Aluche and continued through the night, a police spokesman told AFP.

Some 40 people unfurled the banner and shouted "freedom" from the roof in protest at their detention conditions, an AFP photographer said.

"Following negotiations, they accepted to come down, there was no need for force," the police spokesman said.

Police said the protesters had broken furniture to make their way to the roof, while Spanish daily El Pais reported that some had obstructed security cameras inside the building.

A spokeswoman for city hall said no one had been injured in the riot.

Charities and academics have often denounced prison-like conditions in Spain's seven immigration detention centres -- some of which have overcrowded rooms, dirty toilets and few amenities or translation services.

The centres are meant for people who have come to Spain without a residence permit and are in the process of being deported.

Madrid councillor Javier Barbero, who is in charge of health and safety, described the centres as an "institutional failure".

This is not the first time that immigration detention centres have suffered such incidents.

Earlier this month, 67 migrants without residence permits managed to flee a detention centre where they were being held near the southeastern city of Murcia.

One of the migrants first pretended to be ill, before the others fled as an ambulance arrived.