[elfman2]

Here's the original: http://www.libertypost.org/cgi-bin/readart.cgi?ArtNum=127888&Disp=1#C1

[TChad]

Here's the original

Thanks for the link. Those images confirm my hunch.

While most of the characters are generic, the "S" in many of those signs is written with a distinctive shape that looks like a "5". I think all those signs were written by the same person. Besides the lettering, many of the messages are nearly identical:

"Behead Those Who Insult Islam"
"Annihilate Those Who Insult Islam"
"Massacre Those Who Insult Islam"
"Kill Those Who Insult Islam"

While a couple of signs are partly obscured, it seems a reasonable guess that they say,

"Slay Those Who Insult Islam"
"Butcher Those Who Insult Islam"

Another sign with the characteristic "S":

"Europe. Take Some Lessons From 9/11"

There are more, but their messages are mostly obscured.

Then there are these, both of which have a distinctive "G":

Freedom Go to Hell
Newsnight Go To Hell

So who was responsible for writing the signs?