Investigations into the ongoing wildfires in Hürtgenwald continue, with the cause of the fires remaining unclear.[398540][418890] According to reports from Yahoo Nachrichten and Stern.de, the authorities are working to determine the cause of the fires.[398540][418890] The investigations are ongoing, with no clear reason for the fires yet found.[398540][418890] The European Environment Agency has been involved in the investigation, working to determine the cause of the fires.[398540][418890]