one of them with a machine gun. Before Agent Lackey had a chance to warn his fellow officers, one of the gunmen shouted, "Up, up!" At this instant, Agent Smith, who was in the middle of the back seat, also saw a man with a machine gun to the right of the Plymouth. SAC Vetterli, who was standing at the right front of the Chevrolet turned just in time to hear a voice command, "Let 'em have it!" At this point, from a distance approximately 15 feet diagonally to the right of Agent Caffrey's Chevrolet, an individual crouched behind the radiator of another car opened fire. Officers Grooms and Hermanson immediately fell to the ground, dead. SAC Vetterli, who was standing beside Officers Grooms and Hermanson, was shot in the left arm and dropped to the ground. As he attempted to scramble to the left side of the car to join Agent Caffrey, who had not yet entered the driver's seat of the Chevrolet, Vetterli saw Caffrey fall to the ground. He had been fatally wounded in the head. Inside the car, Frank Nash and Chief Reed were killed. Agents Lackey and Smith were able to survive the massacre by falling forward in the back seat of the Chevrolet. Lackey was struck and seriously wounded by three bullets in the back. Smith was unscathed. The three gunmen rushed to the lawmen's car and looked inside. One of them was heard to shout "They're all dead. Let's get out of here." With that, they raced toward a dark-colored Chevrolet. Just then a Kansas City policeman emerged from Union Station and began firing in the direction of one of the killers, later identified as Floyd, who slumped briefly but continued to run. The killers entered the car which sped westward out of the parking area and disappeared. The three survivors, Agents Smith and Lackey and SAC Vetterli, reported that the assault lasted possibly 30 seconds. They were uncertain if three or four gunmen staged the assault. From their account, it was apparent that the two Kansas City police officers were killed immediately, followed seconds later by Frank Nash and Chief Reed and then by Agent Caffrey, who was taken to a hospital and pronounced dead on arrival. Aftermath The FBI immediately initiated an investigation to identify and apprehend the gunmen. The investigation developed evidence that the scheme was carried out by Vernon