During the commotion, Raphael saw Rat running toward Gardo. Raphael takes off in the other direction, running into traffic and he thinks that the police must have followed him home. Rat thinks the police must have taken their pictures outside the tea-house and offered a reward, meaning somebody gave the boys up. In any case, the next morning, the police show up at the door of where the boys are living.
The police’s actions show that corruption extends far and wide in this society: a reward, it seems can make anything happen, whether the demand is ethical or not.