A video has emerged of a pile-up in the junior Kuurne-Brussels-Kuurne race, caused when the lead car stopped suddenly in front of the peloton.
The crash was filmed from the side of the road and shows riders hitting the back of the car.
Organisers have responded to the incident, saying that human error caused the collision.
Luckily, none of the riders involved were seriously injured.
The race was brought to a halt and restarted after around 20 minutes.
Race director of the junior competition, Maarten Clochet, told Belgian newspaper Het Laatste Nieuws: “It is a human error in the race director’s car.
“The driver has been working for several years but something went wrong with the automatic gearbox of the car, causing it to come to a standstill.
“I held my heart. I thought the race was over but fortunately none of the riders involved suffered a serious injury.
“Everything went well and the race continued after a delay of 21 minutes.”
The race went to Dutch rider Casper van Uden who won the bunch sprint.
British riders also put strong display on Sunday (March 3).
Leo Hayter, Oliver Rees and Lewis Askey finished fourth, fifth and sixth respectively in the bunch kick.
Incidents involving race organisation vehicles hit the headlines sporadically in bike racing.
Belgian revelation Remco Evenepoel, winner of the 2018 junior Kuurne, was involved in a crash at the UAE Tour last week.
The 19-year-old called for race motorbikes to pay more respect to the peloton after the crash.
Mark Cavendish has also been caught in a crash with a race car in the neutral zone of a stage.
In 2018 he was forced to pull out of the Abu Dhabi Tour after the automatic sensors on a vehicle stopped the car, causing him to crash.