At least 28 people, including children, were injured on Sunday when a driver drove his car into a trade union demonstration in Munich, German authorities said, adding that it was believed to be a deliberate attack and that the attacker, an Afghan asylum seeker, had been arrested.

Participants in a demonstration by the service sector workers' union ver.di were walking down a street near the center of Munich at around 10:30 a.m. when a car overtook a police vehicle overseeing the demonstration and drove into the back of the group.

Police have arrested a suspect after shots were fired into a car, Deputy Police Chief Christian Huber said. He added that at least 28 people were believed to have been injured, some seriously. A damaged Mini could be seen at the scene, as well as people's belongings scattered around.

The suspect is a 24-year-old Afghan asylum seeker, Huber said.

Bavaria's governor, Markus Söder, told reporters at the scene that there was a suspicion that it was an attack, "many things point to that," Söder said.