BARRIO (Al Jazeera) – The United States has announced a reward of up to $5m for information into the killing of Ecuadorian presidential candidate Fernando Villavicencio.

“Multiple assassins attacked Mr Villavicencio, the Movimiento Construye party’s presidential candidate in the 2023 elections, as he left a Quito campaign event on August 9,” Secretary of State Antony Blinken explained in a statement on Thursday.

The assassination sent shockwaves through Ecuador, which was, at the time, 11 days away from holding its general elections.

Blinken’s statement comes in the lead-up to a run-off election on October 15 to determine Ecuador’s next president.

“The United States will continue to support the people of Ecuador and work to bring to justice individuals who seek to undermine democratic processes through violent crime,” Blinken said.

Villavicencio, a former journalist, joined the race as an anticorruption candidate after years as a prominent critic of former President Rafael Correa and his allies.

But at the conclusion of his August 9 campaign rally, he was shot in the head as he entered his car. One suspect was also killed, as security at the event returned fire.

Six further suspects, all from Colombia, remain in the custody of the Ecuadorian National Police. They are believed to be part of an organised crime unit, according to Blinken’s statement.

In recent years, Ecuador has been in the grip of escalating violence, particularly after the COVID-19 pandemic significantly weakened the country’s economy.

Experts say gangs have taken advantage of the economic insecurity to expand their reach into Ecuador, a country positioned on the Pacific coast between major cocaine-producing regions in Colombia and Peru.

As a result, the number of homicides has skyrocketed, increasing by 500 percent between 2016 and 2022, according to the Reuters news agency. That puts Ecuador among the countries with the highest rates of murder in Latin America — a stark contrast to Ecuador’s previous reputation as a country with relatively low violence.

The country has also recently endured political upheaval as President Guillermo Lasso became the first president to invoke “muerte cruzada” or “mutual death”, a power set forth in the constitution.

“Mutual death” allows a president to dissolve Ecuador’s National Assembly — if he or she agrees to hold new elections for both the legislature and the presidency.

Lasso announced “mutual death” in the face of impeachment proceedings this past May. He will not be seeking reelection.

Instead, the race has come down to left-leaning Correa protegee Luisa Gonzalez and former National Assembly member Daniel Noboa, a businessman and son of a wealthy banana industry leader.

Security and political violence have been central campaign issues as the final two candidates court voters before the October 15 vote.

Lasso, meanwhile, announced in August that he had sought the assistance of the US Federal Bureau of Investigation (FBI) to help Ecuadorian police investigate Villavicencio’s death.

“The investigation, supported by the FBI, continues to identify others involved in the assassination,” Blinken said on Thursday.