"Baby Face" Nelson killed more FBI agents than any other American criminal. (At least 3) Nelson passionately hated law enforcement and would go out of his way to fight them. On one occasion during a bank robbery, he opened fire without warning on an officer a block away. Laughing he later told his associates (upset by the fact Nelson had turned a controlled situation into a shootout) he did it just because, "I hate cops".
Nelson would eventually be killed in a similar incident. While driving with his wife and an associate, he saw two FBI agents driving the other way. Nelson turned his car around and began chasing the agents. More agents became involved. (Picture a chase with an FBI car, Nelson's car, and another FBI car) Nelson shot it out with the pursing agents, killing both of them but being killed in the process.