A forest fire in the Harz mountains of northern Germany has been fully extinguished after several days of firefighting work in rugged terrain, according to local officials on Wednesday. The fire had broken out on Friday on the Königsberg, a side peak of the Brocken, the tallest mountain in Germany’s mostly flat north. Officials in the nearby city of Wernigerode said on Wednesday that firefighting crews are now being withdrawn and equipment will be dismantled over the next few days. An investigation into the cause of the fire has been launched. At times, the fire front had spread over a length …