Avon & Somerset Police are appealing for spectators with video or photos of the fatal accident to contact them.
The crash happened as 23-year-old cyclist Junior Heffernan came round a bend during the Severn Bridge Road Race.
Here is Acting Inspector Darren Jarvis...
Investigations are continuing into an accident during this weekend's Severn Bridge Road Race, in which a rising cycle star was killed.
23-year-old Junior Heffernan from Devon died after colliding with a car at the side of the road as he came round a bend.
Avon & Somerset Police are appealing for anyone who may have filmed yesterday's race to contact them. They say video of the Severn Bridge Road Race could help with their enquiries into the fatal crash.
They are asking people to contact the collision investigation unit on the force number 101.
Avon & Somerset Police have issued an appeal for witnesses to yesterday's fatal accident.
The crash happened on the B4461 Vattingstone Lane, at its junction with Mumbleys, at Elberton at about 12.45pm.
Junior Heffernan, who was taking part in the Severn Bridge Road Race, was travelling down Vattingstone Lane towards a left-hand bend when he hit a stationary car, which had been travelling in the opposite direction.
Despite treatment, he died at the scene.
Sunday's event (Severn Bridge Road Race) was the first time Junior had raced alongside members of his new team Herbalife Leisure Lakes. The race was immediately abandoned at the request of riders shortly after the incident.
Tributes have been paid to a cyclist who died while competing in the Severn Bridge Road Race in Gloucestershire yesterday. Junior Heffernan was involved in a collision with a car during the race, which was immediately abandoned.
– British Cycling president Brian CooksonThis is a tragedy which will profoundly sadden everyone associated with cycling in this country.
My thoughts are with Junior's family and with his friends.
A cyclist has died while competing in the Severn Bridge Road Race in Gloucestershire. 23-year-old Junior Heffernan from Yelverton in Devon was involved in a collision with a car during the race near Olveston yesterday.
It happened on the third lap of the 10-lap race, which was immediately abandoned.