A car drove into a crowd of people in western Berlin on Wednesday, killing one person and smashing through a shop window, police said, in a district of the German capital popular with tourists and shoppers.
More than a dozen people were injured, a police spokesperson said at the scene. Some injuries were serious, a spokesperson for the fire service added.
"A man is believed to have driven into a group of people. It is not yet known whether it was an accident or a deliberate act," police said, adding that the driver had been detained at the scene.
"We are currently on the scene with about 130 emergency personnel," the police added. "The vehicle, a small car, was secured on site."
Investigators were looking into whether the incident was a deliberate attack or possibly an accident with a medical cause, a police spokesperson said.
Blankets covered what appeared to be a body in a cordoned-off area guarded by police, Reuters images showed. A small, silver colored Renault car was lodged inside a shop after smashing through a plate glass window.
The incident took place next to the war-ravaged Gedaechtniskirche church, one of Berlin's best-known landmarks.
Rescue workers moved apparently conscious people on stretchers towards an ambulance, including one woman sitting up, and another who covered her face with her hand, Reuters images showed.
The site, on a shopping street near a McDonald's restaurant, was cordoned off. Bystanders looked up at a helicopter circling above.