Charles L. Fontenay - Rebels of the Red Planet

The Phoenix had been destroyed not once, not twice, but three times! But this time the resurrected Dark had new plans, plans which involved dangerous experiments in mutation and psionics.

And now the rebels realized they were in double jeopardy. Not only from the government's desperate hatred of their movement, but also from the growing possibility that the new breed of mutated monsters would get out of hand and bring terrors never before known to man. (Summary from Project Gutenberg text)