On April 19 , 1995 Timothy McVeigh carried out the Oklahoma City bombing , which was the worst terrorist attack in U.S. history . McVeigh detonated a Ryder truck bomb at the Alfred P. Murrah Federal Building which killed 168 people . Oklahoma City Police were the first on scene and began rescue efforts . Sgt. Detective Mike McPherson of the Auto Theft Unit and a Bomb Squad member arrived on scene moments after the blast . McPherson assisted the investigators by locating the hidden VIN number on the axle , which later allowed the FBI to tie the truck to McVeigh
Oklahoma City bombing
Oklahoma City bombing
Oklahoma City Police Department