(Of course, you get all the greatness of machine translated Japanese along with it... but it's readable.)
Someone in the #baka-tsuki chat said the poster reads "Don't kill children" or something to that effect. I don't know any french but the caption in that scan seems to agree.
=Smidge=
There's a thread about this on another forum I think. It says 'stop killing the children', and is part of a march in response to a drive-by shootign that killed 3 children a few days ago.
By the way, the picture was taken by a professionnal who got himself injured about a year ago while taking pictures of children throwing stones at israeli soldiers.
This happens a lot. People in that part of the world are pretty well isolated, culturally. The effect is that they often use images they get from who-knows-where and use them in ways that seem peculiar to the rest of us... because they don't know the cultural significance.