Two dogs mauled their owner to death and then dragged his body around his garden before they were both shot dead.
Ruan van Staden suffered serious wound to his head and throat in the attack at his home in Ermelo, South Africa on Thursday.
Paramedics rushed to the scene but were unable to get to 20-year-old van Staden as they feared they would also be attacked.
Two armed security guards managed to chase the dogs away by firing at them but they came shortly after and carried on their attack.
Bester Maree from ACSU Security said when he arrived the dogs had their jaws clutched around Van Staden's neck and head, reports News 24 .
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He said the dogs were dragging van Staden's lifeless body around his garden by thi point and all his clothes had been torn off.
"It was one of the most gruesome sights I have ever seen," he said. "There was blood all over the yard and he was lying in a pool of blood."
Maree said it was still a mystery why the dogs unexpectedly turned on their owner.
Friends and family have posted tributes to the trailer builder on Facebook .
His aunt Lize Mrais wrote: "Van Staden R.I.P. son... dear mercy my heart is broken it's extremely... heartfelt condolences to your dad Lourens Sous VanStaden and mother and sister and to all your loved ones... what do one say to the parents?
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"It's so heartbreaking.
"You were a good boy who always greeted me so beautiful."
Bank Nedbank Namibia, which sponsors cycling events that van Staden competed in wrote: "Nedbank Namibia is saddened by the news of the untimely passing of young Namibian cyclist, Ruan van Staden.
"Ruan was an avid cyclist who competed in a number of Nedbank cycling events.
"Many would agree that the Namibian cycling community has suffered a great loss with his passing.
"We extend our sincere condolences to his family, friends as well as his teammates on the KIA cycling team."
