RIO DE JANEIRO (AP) — At least 12 guards and dozens of inmates were held hostage amid a prisoner uprising in southern Brazil, during which some of the incarcerated were tossed from the roof of the correctional facility.

Despite that, no deaths were yet reported as of late Monday, authorities said, as negotiators worked to end the standoff with inmates who complained of poor treatment and bad food.

At least eight people were reported injured, including six who were thrown from the roof of a building in Guarapuava prison.

It’s the latest uprising at a prison in Brazil, where severely overcrowded conditions and poor security lead to several such rebellions each year. In late August, rebelling inmates beheaded two prisoners during an uprising in the same state where Monday’s action occurred.

The uprising at the prison housing nearly 250 inmates began when an estimated 40 inmates on a work detail over-powered guards.

Live television images showed hooded prisoners armed with knives and clubs on the roof of a prison building, making threatening gestures toward disrobed guards, whose hands were tied behind their backs.

The Parana state justice secretariat, in charge of prisons, says its director is negotiating directly with the inmates holding the guards and fellow prisoners captive.

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