The Port Neal fertilizer plant explosion Attack occurred Coming_to_be on December 13 , 1994 in the ammonium nitrate plant at the Terra International , Inc. , Port Neal Complex , 16 miles south of Sioux City , Iowa , United States .

The Santa María School massacre was a massacre Killing of striking workers , mostly saltpeter works ( nitrate ) miners , along with wives and children , committed Committing_crime by the Chilean Army in Iquique , Chile on December 21 , 1907 .

It occurred Presence during the peak of the nitrate mining era , which coincided with the Parliamentary Period in Chilean political history ( 1891–1925 ) .

The site of the massacre was the Domingo Santa María School , where thousands of miners from different nitrate mines in Chile 's far north had been camping Traveling for a week after converging on Iquique , the regional capital , to appeal Request for government intervention to improve Cause_to_make_progress their living and working conditions .