Hundreds of people demonstrated in the western German cities of Mannheim and Heidelberg on Tuesday evening after a man died during a police operation. Many more demanded an investigation into what caused the death of the 47-year-old man who was stopped by police in central Mannheim on Monday. When the man refused to cooperate, the police officers overpowered him, the Baden-Württemberg state office of criminal investigation (LKA) and the Mannheim public prosecutor’s office said. In videos shared later online, one officer appeared to hit the man in the head. The LKA said officers deployed the us…