Sounds like an individual act of violence, possibly a hate crime
It doesn't really appear to an act of an organized terrorist group. Probably just a hate filled individual, whatever his background, lashing out rather stupidly at Jews, Israelis, Americans, or whoever his specific target was.
Who knows, maybe this nutcase is right now being happily serviced by 72 virgins in his particular Paradise, courtesy of the highly professional and efficient El Al security agents, whose quick and courageous actions surely prevented more deaths in the attack.