The justice secretary said the prisoners died overnight at the Agricultural Penitentiary of Monte Cristo.
Police said officers had been deployed to the prison.
The bloodshed comes days after rebellions in other two prisons left 60 dead in the neighbouring state of
Amazonas.
Authorities said gangs are fighting for control of drug routes in the northern part of the country, which borders Colombia, Venezuela, Peru and the Guianas.
In Amazonas, several of the prisoners were decapitated during a rebellion on Sunday and Monday.