Ammonium nitrate was developed as part of a 'quest' for bigger explosives. In 1659, ammonium nitrate was synthesized by John R. Glauber for the first time as part of a reaction with ammonium carbonate and nitric acid. During World War I, ammonia plants were build to supply Germany with explosives. These plants formed ammonia using the Haber-Bosh process which combines hydrogen and nitrogen under high pressure. At the end of the war, there was a large surplus of ammonium nitrate which was in a huge pile. To break it apart explosives were drilled into holes in the pile. It was expected to break apart, much the same as rock does. Instead, the pile of 4,500 tons (Oklahoma City was 2 tons) detonated and killed 600 people.

Ammonium nitrate and fuel oil accounts for about 95% of all commercial explosives work. Collectively, the substance is called ANFO (Ammonium Nitrate and Fuel Oil) and is known for its power and relatively safely (it cannot explode spontaneously and contains no volatiles such as nitroglycerin).

On August 19, 1970 - at 3:40 am in the morning, Karl Armstrong, Dwight Armstrong, David Fine, and Leo Burt set off a bomb made with ammonium nitrate in a stolen van outside Sterling Hall in the University of Wisconsin Madison. The time was chosen in an attempt to minimize injury to people - however, Robert Fassnacht (a graduate student working late to finish a project before going on vacation with his wife, three year old son and twin one year old daughters) was in the building at the time and killed. Four other people were injured in the blast.

The top three floors of Sterling Hall housed the Army Mathematics Research Center that was a target for anti-war demonstrators. Within Army Math, research regarding the patterns of dispersal for viral agents, the effect of anthrax, and survival probability in a bunker. There were rumors that infrared surveillance techniques where developed there that were used in the assassination of Che Guevara and secret research projects that would be used to kill civilians in Southeast Asia.

Karl, Dwight, David and Leo were known as the New Year's Gang after an attempt to bomb Badger Munitions near Baraboo, Wisconsin on January 31. Flying over the plant, they dropped a mayonnaise jar that had been filled with ammonium nitrate and fuel oil out of the window of a stolen plane. The bombs were duds.

The blast itself damaged Sterling Hall and the buildings surrounding it. Windows were blown out of buildings several blocks away. Pieces of the van were found on top of an eight-story building three blocks away. The blast was heard as far away as 30 miles. At the time, it was the most destructive act of terrorism upon American soil.

The bombing of Sterling Hall turned the public feeling against the anti-war movement. Prior to August 19, 1970 there were several thousand (often in the 10-15 thousand range) people rioting in Madison on a weekly basis. Following August 19 it fell to less than a thousand. Professors who had previously been activists declined to give lectures other than academic ones.

Karl, Dwight, and David have served prison sentences. David Fine has earned a law degree, Dwight Armstrong works for Union Cab in Madison. Karl Armstrong runs a drink stand in the Library Mall on the university campus. The whereabouts of Leo Burt are still unknown though he is no longer on the FBI's 10 most wanted list.

April 19, 1995 at 9:03 am in Oklahoma City a bomb went up outside of the Alfred P. Murrah Federal Building. The blast killed 168 people (19 of which were children) and injured over 500 others. The truck bomb went off just as parents were dropping off children at the day care center in the Murrah Federal Building. A list of the victims can be found at

The bomb itself was made with two tons of ammonium nitrate and fuel oil and put in the back of a Ryder truck. The blast destroyed the front of the federal building. Collapsed floors buried many of the victims.

In the fall of 1994 a "Mike Havens" purchased 80 50 pound bags of ammonium nitrate (fertilizer). The receipt for the bags where found wrapped around gold collector coins found in a search of Nichols' house.

The bombing was in part motivated by the 1993 raid by the Bureau of Alcohol, Tobacco, and Firearms upon the Branch Davidians. The standoff ended on April 19, 1993 when the FBI entered the compound and the buildings caught fire. The blast occurred on the second anniversary of that event.

McVeigh was pulled over 90 minutes after the explosion for driving without a license plate. At the time he was also carrying a firearm and for these two offenses he was sent to jail. Shortly before he was due to be released on April 21, he was recognized as the bombing suspect and charged with the bombing. In June 1997, Timothy McVeigh was found guilty of conspiracy and eight counts of manslaughter. He was sentenced to die by lethal injection which was carried out on June 11, 2001 at 7:14 am.

Terry Nichols was at home in Kansas when the bomb went off and turned himself in two days later. Nichols was convicted of involuntary manslaughter and conspiracy to use a weapon of mass destruction December 23 (he was found not-guilty for using a weapon of mass destruction and destruction by explosive). Nichols avoided the death penalty because there was question about if he was planning the attack with attempt to kill and was instead sentenced to life in prison without parole. Nichols was also sentenced to 48 years for eight counts of involuntary manslaughter (eight federal agents) and ordered to pay $14 million for damage caused to the building.