Dramatic footage of a prison break in Brazil in which inmates hold guards and fellow prisoners hostage.

The inmates wearing white masks were seen parading 12 officers to the building's rooftop. They were then blindfolded, and beaten.

One guard was strung up by his feet, and hung upside down over the side of the building.

The inmates are demanding better sleeping conditions, and food and the use of mobile phones.

The prison is at full capacity with 240 inmates. Officials say at least 150 prisoners are also being held hostage.