A man was killed and four others seriously injured — two of them critically — after an explosion in a pedestrian tunnel in Völklingen (a small city near Saarbrücken in southwestern Germany) in the early hours of this morning. The five men were found shortly after midnight in the underground walkway in the city centre, with one dying at the scene and four taken to hospital. Police believe the men triggered the blast themselves, though the cause and circumstances remain under investigation.