Berlin, Germany: One man was killed and four others seriously injured in a powerful explosion inside a pedestrian tunnel in Volklingen, western Germany.
German police said the injured include two men in life-threatening condition. Investigators believe the blast was caused by human action, without providing further details.
A security cordon has been imposed around the site as authorities continue efforts to determine the cause. Volklingen, with a population of around 40,000, lies near the French border.
