Reuters

Fredy Salcedo / EPA

A group of prisoners stand on the roof of Socabaya prison during a riot in Peru's southern city of Arequipa, Tuesday, August 28, 2012. About 200 prisoners started a mutiny in the early hours of the day, injuring prison guards and taking four hostages, including the prison director, according to local media. All hostages were later released, and the riot continues as the prisoners demanded improvements of prison conditions and medical attention, said local reports. The banner reads, "Freedom. Benefits."

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Carlos Garcia Rawlins / Reuters

Relatives of inmates pray outside the La Planta prison in Caracas, April 30, after riots erupted inside the prison.

Carlos Garcia Rawlins / Reuters

Relatives of inmates cry outside the La Planta prison in Caracas, April 30, after riots erupted inside the prison. Gunshots and explosions were heard inside the prison after a plan for a massive escape was discovered by guards.

 Authorities discovered a tunnel  on Friday leading out of the La Planta prison in Caracas which they believe was constructed for an escape attempt. Today, relatives waited anxiously outside for news after explosions and gunfire were heard inside the prison.

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Julio Cesar Aguilar / AFP - Getty Images

Relatives of inmates at Apodaca prison, attempt to trespass the security fence following a riot inside the prison, on February 19, near Monterrey, Mexico. At least 40 inmates have been killed during a riot.

Julio Cesar Aguilar / AFP - Getty Images

Relatives of inmates cry while waiting outside Apodaca prison, Feb. 19.

Nuevo Leon state public security spokesman Jorge Domene Zambrano said the riot broke out at about 2 a.m. in a high-security section of a prison in the city of Apodaca outside of the northern industrial city of Monterrey.

A group of inmates in one cell block started to riot and took one of the guards hostage, Domene said. The riot then spread to a second cell block, and at least 40 people died before authorities regained control of the prison a couple of hours later.

-- Reported by the Associated Press

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