The former driver of Chilean Nobel laureate Pablo Neruda -- who sparked claims the poet's 1973 death was due to poisoning -- died Tuesday, the Communist Party of Chile announced.
Manuel Araya died in the city of San Antonio aged 77, it said.
Neruda was a celebrated poet, politician, diplomat, and bohemian figure, and also a prominent member of Chile's communist party when former military dictator Augusto Pinochet took power in a 1973 coup.
He had been preparing to flee into exile in Mexico to lead the resistance against the Pinochet regime when he died in hospital just 12 days after the coup.
The government claimed the 69-year-old had died of prostate cancer.
An investigation into the cause of Neruda's death began in 2011 when Araya -- his driver and personal assistant -- asserted that the poet was given a mysterious injection in his chest just before he died.
In 2017 a group of Chilean and international experts concluded that Neruda did not die of cancer but said they could not determine what did kill him.
"Manuel Araya was key with his testimony... and his courage to us having the elements" that gave rise to an investigation, the party statement said.
In February, two members of a scientific panel investigating Neruda's death told AFP they could not determine whether he had been poisoned.
The panel has delivered a report to a judge, and the country is waiting on tenterhooks to hear its conclusions.
Pinochet, who ruled Chile for 17 years, oversaw a regime that killed some 3,200 leftist activists and other suspected opponents.
The dictator died in 2006 aged 91 without ever being convicted for crimes committed by his regime.
Neruda is remembered especially for sensual poems about love.