Insurgent

One who participates ip an insurrection; one who opposes the execution of law by force of arms or who rises in revolt against the constituted authorities. A distinction is often taken between "insurgent" and "rebel," in this: that the former term is not necessarily to be taken in a bald sense, inasmuch as an insurrection, though extralegal, may be just and timely in itself; as where it is undertaken for the overthrow of tyranny or the reform of gross abuses. According to Webster, an insurrection is an incipient or early stage of a rebellion.