Hero or Murderer

Here is the Scenario:
OKLAHOMA CITY – Confronted by two holdup men, pharmacist Jerome Ersland pulled a gun, shot one of them in the head and chased the other away. Then, in a scene recorded by the drugstore's security camera, he went behind the counter, got another gun, and pumped five more bullets into the wounded teenager as he lay on the floor.

Now Ersland has been charged with first-degree murder in a case that has stirred a furious debate over vigilante justice and self-defense and turned the pharmacist into something of a folk hero.



When I heard about this I thought that the pharmacist did what he he had too. However after watching this video has changed my mind completely. This guy was definitely in the wrong. What do you think?