The accident occurred when one of the carriages in the roller coaster braked sharply, according to the British television channel.
This must have led to another wagon crashing with the crew in front.
Several helicopters and ambulances have picked up injured people in the amusement park, which is located in the city of Günzburg.
Just over half of the injured must have been in need of hospital care.
This weekend, a woman died in an accident at another amusement park in Germany.
She is said to have, for an unknown reason, fallen out of a roller coaster car,