General Gary Prado Salmón, who as a Bolivian army captain led the operation that captured Argentine revolutionary Che Guevara, a critical ally of Fidel Castro’s in the Cuban revolution, in 1967, died on May 6 in a hospital in Santa Cruz, Bolivia. He was 84.

His son Gary Prado Arauz announced the death on Facebook but did not give a cause.

After leaving Cuba in 1965, Guevara tried and failed to ignite a communist revolutionary movement in what is now the Democratic Republic of the Congo, and then he and other guerrillas headed to Bolivia the next year in hopes of overthrowing the government of President René Barriento Ortuño, a general who had taken control of the country in a coup.

Captain Prado and his men – part of a CIA-backed special forces unit – had been hunting the guerrillas for months when he received a tip from a farmer, an old friend from school, who said he had seen them in a deep ravine near the small village of La Higuera.

At 1 pm on October 8, 1967, Captain Prado heard shouts from the ravine: His soldiers had captured two guerrillas.

When one of them surrendered, General Prado later told the New York Timeshe shouted, “I am Che Guevara, and I am worth more to you alive than dead.”

Mr. Guevara had been wounded in the battle, his gun broken.

“He presented a pitiful figure, dirty, smelly and rundown,” General Prado said in an interview with FT Magazine in 2017. “He had been on the run for months. His hair was long, messy and matted and his beard bushy.” And, said General Prado, “He had no shoes, only remnants of animal skin on his feet.”

Mr. Guevara was kept in a room in a small schoolhouse in the nearby village of La Higuera, where he spoke several times with Captain Prado. Asked why he fought in Bolivia, Guevara said: “The revolution has no limit.” Captain Prado told him he had come to the wrong country, which he said had undergone its own revolution through agrarian reform and the nationalization of its mines.

“Then came his concern for his future,” General Prado told CE Noticias Financieras English newspaper this year. “‘What will happen to me?'” I told him he will be brought to justice.

But the next day, after Captain Prado left to pursue other guerrillas, he said, Guevera was executed by an army sergeant on the orders of President Barrientos. Captain Prado returned in time to help strap down Mr. Guevera’s body to the runners on a helicopter that took it to nearby Vallegrande.

“He was then laid out on a concrete slab in the small laundry room behind the hospital, and about 30 press photographers from all over the world were invited to take pictures of the body as it lay in state,” General Prado told FT Magazine. “It was important for the government and the military to show Che’s death as a lesson to anyone who intended to invade or threaten the Bolivian way of life in the future.”

General Prado eventually wrote two books, “How I Captured Che” (1987) and “The Defeat of Che Guevara: Military Response to Guerrilla Challenge in Bolivia” (1990).

General Prado wrote two books about his capture of Che Guevara.

Gary Augusto Prado Salmón was born on November 15, 1938, in Rome, to Julio Prado Montaño, a Bolivian army officer on assignment in the city, and Adela Salmón Tapia. At 15, after the family had returned to Bolivia, Gary enrolled in the military academy and graduated as a second lieutenant in 1958. He became an instructor at the college.

In 1974, seven years after the capture of Guevara made Captain Prado a military hero, he was arrested as one of the leaders of an uprising against President Hugo Banzer Suárez’s military dictatorship. A year later, however, he was reinstated.

In 1981, by now a colonel commanding the army’s Eighth Division, he led the recapture of an Occidental Petroleum natural gas plant in Santa Cruz that had been held by ultra-rightists who had threatened to blow it up unless Bolivia’s military junta resigned.

But it would be Colonel Prado’s last active operation: He was paralyzed by a bullet to the spine fired by one of his own men. Citing a witness’ account, The Miami Herald reported that he had been shot by a second lieutenant in what Colonel Prado said was an accident.

Colonel Prado was eventually promoted to the rank of general, but the injury, which left him in a wheelchair, blocked his path to becoming the army commander he had once hoped for. He retired from the military in the late 1980s and then served as Bolivia’s ambassador to the United Kingdom and later to Mexico.

Information on his survivors was not immediately available.

Some Mexican admirers of Mr. Guevera opposed General Prado’s appointment as ambassador. During a reception at a Mexican cultural center in 2001, Alberto Hijar, an art critic, threw a glass of wine at General Prado and shouted, “To the health of Che!” Mr. Hijar told the Chicago Tribune“He’s a war criminal.”

But General Prado told The Tribune: “I have acted correctly in my entire life, not just in this episode. I don’t need to be ashamed or hide.” He tried to minimize the importance of capturing Mr. Guevera, adding: “All that incident is hardly four lines in the history of Bolivia.”