German police say four people have been injured in a stabbing attack at a commuter rail and subway station in downtown Frankfurt. Frankfurt police spokeswoman Chantal Ench said the attack took place Saturday afternoon inside the Hauptwache station. Ench says four people were taken to the hospital with stab wounds, but she didn't have details beyond that. She says police are investigating to find out how many people were involved. She also didn't have any details on the ages and genders of the injured.