At least 68 people were killed in rioting and a fire at a police detention center in the city of Valencia late on Wednesday, Venezuela's top prosecutor said.

"In light of the terrible events that took place in the Carabobo state police headquarters, where 68 people died in a presumed fire, we have appointed four prosecutors ... to clarify these dramatic events," Tarek William Saab wrote on Twitter.

Local government official Jesus Santander said that the state of Carabobo would observe a period of mourning for the dead.

Relatives of some of the detainees said that the prisoners were kept in squalid and unsafe conditions. Venezuelan prisons are known for being overcrowded, filled with drugs and weapons.

Some of these relatives clashed with police after they stormed to the scene, demanding to know if their loved ones were still alive. National guard troops carrying rifles and wearing bullet-proof vests were deployed to the scene, keeping the families away from the building.

According to the nonprofit A Window to Freedom, rescuers had to break through solid walls to try and reach some of the victims trapped inside the building. The group said that small jails have also begun suffering overcrowding recently as detainees are held for much longer than the customary short-term jail visit before being sent either home or to trial.

"There are people who are inside those dungeons ... and the authorities do not know they exist because they do not dare to enter," said Humberto Prado, a local prisons rights activist.

Violent riots often break out in Venezuelan jails due to the ready availability of weapons received from corrupt guards.

es/bw (AFP, Reuters)

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