Kirby: This idea that just, there's no vetting, and there's no proper immigration enforcement going on at the border, just does not comport with reality.

Reporter: Up until today, US Policy then, has been, 'we don't negotiate with terrorists', but we will give them hundreds of millions of dollars.

Kirby: Come on now, that's conflating here. That's like saying the whole UNRWA [United Nations Relief and Works Agency for Palestine Refugees] is a terrorist organization…if the investigation proves that, in this case I think it's about a dozen employees were assisting Hamas, and even to the point of maybe even involved in hostage taking, then absolutely they need to be held to account.