Ben Horton: Monster Republic: The Judas Code [2011] paperback

The explosion at the Prime Minister's visit to Long Harbour means the cover of the Monster Republic is blown, and they are forced deep into hiding. Lazarus Fry turns his tactics to infiltration, and is confident of their swift crushing. Plus his new pets, the Blood Hawks, are hungry to get their talons into some fresh kill...
But Fry hasn't counted on this band of rebel kids' awesome will for survival. When your back is against the wall, the only option is to come out fighting...