- Iranian Bahman Golbarnezhad was 48
- He suffered a cardiac arrest on the way to hospital
(CNN)An Iranian Para-cyclist has died following a crash in the men's road race Saturday.
Bahman Golbarnezhad crashed on the downhill slope of the C4-5 classification road race.
"The athlete received treatment at the scene and was in the process of being taken to the athlete hospital when he suffered a cardiac arrest," said the International Paralympic Committee (IPC).
"The ambulance then diverted to the nearby Unimed Rio Hospital in Barra where he passed away soon after arrival."
Forty-eight-year-old Golbarnezhad had also competed in the London 2012 Paralympics.
"The Paralympic family is united in grief at this horrendous tragedy which casts a shadow over what have been great Paralympic Games here in Rio," said the IPC president Sir Philip Craven.
"This is truly heart-breaking news and the thoughts and condolences of the whole Paralympic Movement are with Bahman's family, friends, and teammates as well as the whole of the National Paralympic Committee (NPC) of Iran."
The IPC's director of media and communications Craig Spence added: "A truly heartbreaking and tragic day and one I hope I never have to experience again."
Moment of silence
The IPC said it had launched an investigation into the circumstances of the crash.
It took place on the first section of the Grumari loop, "a mountainous stretch of the course", according to the IPC.
Last month during the women's road race in Olympic Games, Dutch cyclist Annemiek van Vleuten crashed while leading the race on a different course with just 11 kilometers to go.
Van Vleuten flew head-first over her handlebars as her hopes of a first Olympic title disappeared. She suffered three spinal fractures and concussion.
The Dutch cyclist crashed on the same descent that left Italy's Vincenzo Nibali with two broken collarbones in the men's race.
On Wednesday, Golbarnezhad had finished 14th in the time trial event.
At the Paralympic Village the Iranian flag has been lowered to half-mast and a moment of silence will also be held for Golbarnerzhad during Sunday's Closing Ceremony.
"This is very sad news for sport and for the Paralympic movement," said Carlos Nuzman, President of Rio 2016. "Our hearts and prayers are with Bahman's family, his teammates and all the people of Iran."
Tributes poured in for the Iranian on social media as other athletes finished their events in athletics and swimming, unaware of the tragedy.
"RIP to a true fighter, so sad to hear he did it doing what he loved," wrote Adam Whiteley on Twitter.
"A tragic, tragic end to a fantastically inspiring paralympics. So, so sad," posted Joel Dunn-Wilson.
Golbarnerzhad took up para cycling in 2002.