Using if statement inside IEnumerator freezes unity

Okay so here is the code

IEnumerator LookingForTarget() { for (;;) { if (TargetsCount > 0) { ShootingState(); StopCoroutine("LookingForTarget"); } else { yield return new WaitForSeconds(.5f); } } }

In the game, whenever someone is at the player´s range, it goes into that "targets" list. By using this code i wanted to control the reaction time of the player so he´s not actively looking for a target all the time. But when i run unity everything goes nice until a target its at range, because unity freezes. I´ve been putting different Debug.Log´s in the code to see where the program stops and it seems like anything i write after that if statement is not executed if the statement is true... Thanks in advance