A stalled motorcycle caused a large pile-up near the start of the last event of the Red Hook Criterium bike race in Brooklyn Saturday night, according to video of the crash.
The video shows a pacer motorcycle stall in the path of the race soon after the bikers took off. The motorcyclist looks back, but does not dismount from his bike while cyclists swerve to avoid him.
One of the racers then hits the motorcyclist, crashing to the ground and causing what appears to be dozens of cyclists to hit the pavement.
The Red Hook Criterium has been raced in Brooklyn since 2008. Bikers in the race pedal fixed-gear bikes around a brakeless track, according to the race's website.