What happened was a tragedy but from the sounds of this mans character he does not sound like he intended to murder anybody. You can be trained HOW to react to situations but until your actually in the situation you don't know how you WILL react. Its possible adrenaline took over or instincts replaced good judgement. There needs to be an investigation but hopefully is was not murder but for now the only thing that matters is the dead.
Reformists are in the lead in Iranian parliamentary elections (dpa)
from the article: Security guard shoots, kills Jewish Israeli man at Western Wall