On April 19, 1995, a truck bomb explosion outside the Alfred P. Murrah Federal Building in Oklahoma City, Oklahoma, left 168 people dead and hundreds more injured. The blast was set off by anti-government militant Timothy McVeigh, who in 2001 was executed for his crimes. McVeigh had been a U.S. militia movement sympathizer who was a Gulf War veteran. He detonated a Ryder rental truck full of explosives parked in front of the federal building. McVeigh's co-conspirator, Terry Nichols, had assisted in the bomb preparation. Motivated by his hatred of the federal government and angered by its handling of the 1993 Waco siege and the Ruby Ridge incident in 1992, McVeigh timed his attack to coincide with the second anniversary of the deadly fire that ended the siege at the Branch Davidian compound in Waco, Texas.

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