PRETORIA, SOUTH AFRICA (NBC) — Oscar Pistorius has been treated for minor wrist injuries at a hospital in South Africa.

The former Olympian told officials that he suffered the injuries after falling off his bed, and denied speculation of a suicide attempt.

Pistorius, known as the “Blade Runner” for his carbon-fiber running blades, is serving a six-year sentence for killing girlfriend Reeva Steenkamp.

He gained worldwide fame when he ran against able-bodied athletes at the 2012 London Olympics.

He was the first amputee runner to compete at the games.

South African prison officials said Sunday that Pistorius was returned to prison Saturday, and an investigation is underway.

He was initially treated by medical staff at the prison, and then transferred to a hospital.

Pistorius’ family declined to comment, referring inquiries to the correctional services department.

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