What about the Boer Wars?
During these wars between the British Empire and the Orange Free State and the Transvaal Republic, the British Army pursued the policy of rounding up and isolating the Boer civilian population into concentration camps.
During the second Boer War, the Boer commanders adopted guerrilla warfare tactics, primarily conducting raids against infrastructure, resource and supply targets, all aimed at disrupting the operational capacity of the British Army. Their tactics were to strike fast and hard causing as much damage to the enemy as possible, and then to withdraw and vanish before enemy reinforcements could arrive.
In response, the British Army used armoured trains, established fortified blockhouses at key points and started the scorched earth policy of Roberts and Kitchener.
The concentration camp system was the first time that a whole nation had been systematically targeted, and the first in which some whole regions had been depopulated.