Jeffrey Thomas: Blue War [2008] paperback

It is a jungle of blue vegetation, in another dimension. Over a decade earlier, Earth’s Colonial Forces battled against the blue-skinned Ha Jiin people, in order to help support the autonomy of the Jin Haa people. An attempt to grow an apartment village from an organic material has strangely led to the Earth colony of Punktown being replicated at an astonishing rate. More strangely yet, a Ha Jiin security patrol finds three clones that the organic city seems to have regenerated from long dead remains. Jeremy Stake is called in to solve the mystery and he soon finds himself trying to prevent another war.