Answer:
Through a secret and very violent police.
Step-by-step explanation:
The Political-Social Brigade (BPS), whose official name was the Social Investigation Brigade (BSI), was the secret police that existed in Spain during the dictatorship of Francisco Franco, in charge of persecuting and repressing all movements of the opposition to the Franco regime. . Organically constituted a section of the General Police Corps (CGP). After the death of Francisco Franco, during the years of transition the brigade was restructured and replaced by the Central Information Brigade (BCI). Among the anti-Franco opposition was commonly known as "The Social", "The Secret" or "The Brigade."