Mario Teran entered history as the young army sergeant who was chosen to execute the captured guerrilla on October 9 1967, an act which marked him as a villain to those who revered Che. Almost four decades later the ageing, retired executioner had his cataracts removed by a Cuban-run medical programme which showcases the benefits of the island's socialist revolution.

The ironic epilogue to Mr Teran's role in a great 20th century drama was first revealed last year when his son wrote a letter to a Bolivian newspaper, El Deber, to thank the doctors. Few people noticed, however, until last weekend when Cuba's communist authorities trumpeted the news as a propaganda coup on the eve of the anniversary of Che's death.

"Four decades after Mario Teran attempted to destroy a dream and an idea, Che returns to win yet another battle," said Granma, the Communist party's official newspaper. "Now an old man, he [Teran] can once again appreciate the colours of the sky and the forest, enjoy the smiles of his grandchildren and watch football games."

It was not immediately possible to reach Mr Teran or his son yesterday, but an editor at El Deber, Leopoldo Vega, confirmed that the letter was published last year.

Mr Teran was treated under Operation Miracle. Funded by Venezuelan petro-dollars and staffed by Cuban doctors, it offers free eye treatment to poor people across Latin America.