Two cars collided on the Oudestreek in Zevenhuizen, just across the provincial border. One of the cars lost a rear wheel, while the other car also hit a tree.
Ambulance personnel quickly arrived to provide assistance to all occupants. Four people have been taken to hospital.
Both cars were severely damaged after the accident and are being recovered. Other traffic can temporarily continue its way along the cycle path.
It is not known how the accident could happen.