BERLIN — A German man who drove his car into a crowd celebrating Carnival, injuring dozens of people including many children, is being investigated on suspicion of attempted murder, prosecutors said Tuesday. The 29-year-old man, who suffered serious head injuries in the crash, lived in the central German town of Volkmarsen, where the incident took place Monday. Authorities said 61 people were injured when the man plowed into a crowd watching the traditional “Rose Monday” procession, including 20 children.