The mayor of a mining town in southern Ecuador was shot dead Friday, the second in days ahead of a weekend referendum on tougher measures against violent crime, police said.

Jorge Maldonado, the mayor of Portovelo, "fell victim to gunshots that resulted in his death," police said on social network X.

This made him the fifth Ecuadoran major assassinated in a year, and the third in a month.

Two days before Maldonado's killing, the mayor of Camilo Ponce Enriquez in the southern province of Azuay, Jose Sanchez, was shot and killed.

Millions of Ecuadorans will cast ballots in a referendum on Sunday to decide whether or not to green-light stricter measures against organized crime in a country gripped by bloody gang wars.

Once a bastion of peace situated between major cocaine producers, the South American country has been plunged into crisis after years of expansion by the transnational cartels that use its ports to ship the drug to the United States and Europe.

Prosecutors, journalists and police are also among the victims of organized criminals with links to Mexican and Colombian cartels.

In January, President Daniel Noboa declared a state of "internal armed conflict" against about 20 criminal groups.

That came after a spasm of violence sparked by the prison escape of a major drug lord, who has yet to be recaptured.