The explosion of 1948

 "The clock at Gate 1 stopped at 3:43 p.m. The explosion that shook the BASF site in Ludwigshafen at this time on July 28, 1948 wrought unthinkable destruction in a place that was still being rebuilt following the Second World War and which was still under French occupation three years after the end of the war. The disaster created a widespread stir as a result of extensive international press coverage. Similarly, aid also came from virtually all over the world after the explosion, and soldiers from both the French and the adjacent American occupation zones immediately made their way to the site to assist."

Read about the incident in this link