What kind of rule of law is that? It is entirely possible (and quite likely) that many members were not at all involved in these activities. Further more the people you do want to fine must have broken some kind of law (and the state must prove this), you can't just invent crime and punishment retroactively. An extension of the freeze sounds like a nice idea though.
Rocket attack kills 15 in Yemen hotel for officials, troops (AP)
from the article: Settlers block West Bank roads to protest construction freeze