An atheist can be considered agnostic if you force him to make proper logic reasoning, whereas he'll acknowledge that in fact you can't prove the existence or not of such entities. But in the end of the day his urge to deny such existence will always make of him an atheist, disregard the previous event, abandoning the mentioned logic train of thought.
Other than that, I believe it's pretty hypocritical to promptly deny the possibility of existence of such entities (atheism) with all the limitations we have to prove such, where the counterpart (theism), so far, is merely delusional, the perfect "scapegoat" when one cannot cope with reality and the fact that shit indeed tend to happen, there's a paraphernalia of events that can be triggered by chance, and this very definition scares the shit out of a "believer".