GUAYAQUIL, Ecuador, Oct 8, 2023 (BSS/AFP) - A seventh Colombian prisoner accused in the August assassination of Ecuadoran presidential candidate Fernando Villavicencio has died behind bars, authorities in Quito said Saturday, as top security officials were sacked.

Ecuador's prison authority said in a statement that the Colombian who died in the capital's El Inca prison -- like the six killed Friday in a prison in port city Guayaquil -- was "linked" to the murder of presidential candidate and anti-corruption crusader Villavicencio.

President Guillermo Lasso on Saturday announced a "reorganization" of the country's police leadership, with the force's general commander, investigations chief and prisons director removed from their posts.

Lasso's office also said it will file a criminal complaint against the director of the Guayaquil prison, where the prisoners were said to have died amid "disturbances."

"He has already been detained... to give his version before the prosecutor's office," the presidency said.

Authorities have not provided details on the inmate deaths, nor explained how the Quito prison failed to provide extra protection for the seventh suspect following Friday's killings.

The assassination of Villavicencio, a centrist who had been polling in second place, rocked Ecuador days ahead of the August 20 national elections in which corruption and the country's declining security situation were major themes.

Six Colombians with long criminal records were arrested shortly after, while one was killed at the scene of the crime. Authorities arrested seven others days later.

The suspects' deaths come just over a week before the election between leftist frontrunner Luisa Gonzalez and challenger Daniel Noboa.

The winner of the October 15 vote will succeed Lasso, who called snap polls to avoid possible impeachment for embezzlement.

- Key election issue -

Villavicencio had carried out scores of investigations, including exposing a vast graft network which led to former president Correa being sentenced to eight years in prison.

Correa fled the country to avoid jail time and has been living in exile in Belgium for six years.

Villavicencio had drawn the ire of gangs and drug traffickers with his reputation for speaking out against the cartels, many of which operate out of prisons across Ecuador.

Ecuador was once a peaceful haven nestled between the world's largest cocaine producers -- Colombia and Peru.

However, the war on drugs in other South American nations displaced drug cartels to Ecuador, which has large Pacific ports, widespread corruption, and a dollarized economy.

Guayas 1, where the five inmates were killed Friday, houses some 6,800 inmates. It is one of five facilities that make up a large prison complex in Guayaquil, a key port city that has become one of the country's increasingly bloody centers of a turf war between rival drug-trafficking gangs.

More than 430 inmates have died violently since 2021, dozens of them dismembered and incinerated amid disputes between rival gangs.

In late August, dozens of guards were taken hostage at several prisons around the country before eventually being released.

On Ecuador's streets, homicides have quadrupled between 2018 and 2022, climbing to a record 26 per 100,000 inhabitants.

The prisons crisis has become a key point of debate ahead of the second round election, with Noboa proposing holding the country's most violent prisoners on ships offshore.