In Guatemala, and in fact in Ireland decades earlier, the guerrillas depended on the support of the local population. Because the army could not identify and target the guerrillas directly, they used a strategy of collective punishment against villagers. The idea was that the local people would turn against the guerrillas if they suffered because of the rebels’ resistance.
To make this strategy as effective as possible, the army was extremely brutal and sadistic against the civilian population. This has become a typical strategy used against guerrilla rebels. Any time the army suffers an attack by guerrillas, they punish the local population.