(CNS) Nine prisoners and two guards were killed during a riot in a prison in the western Vealnnezuelan state of Lara, Prisons Minister Iris Varela told reporters on Friday, in the country’s second prison riot within a week.

The latest riot at the Fenix prison, which took place on Thursday, is now under control and will be investigated by the prosecutor’s office, Varela said.

The incident came a day after a Wednesday clash between inmates at the Helicoide prison complex in Caracas, where several prominent opponents of President Nicolas Maduro’s socialist government are held. No one died in that incident.

Varela added that Joshua Holt, a U.S. citizen and Mormon missionary who is jailed in the Helicoide and pleaded for help on social media during that incident, was still incarcerated.

The Helicoide revolt prompted the U.S. government to call for his release.

Prisons in Venezuela are awash with weapons and drugs, and violence inside pre-dates the current economic crisis.

Nearly one million Venezuelans left the country between 2015 and 2017, according to the United Nations, amid rampant inflation, insecurity as well as food and medicine shortages.