Young Detective - Take 1

A person suspects there is one mastermind behind recent attacks. They believe the one who attacked City Hall is the suspect. The same markings were found at the docks and the mill. The attacks were kept in the north, but City Hall changes things. They want to find out who left a brick to find the person behind it all. They realize their friend is wearing a government official seal and accuses them of being one of the attackers, like their parents. They tell them to leave. Did anyone see you come up here? Shh! Don't answer that. Ah, you've had a brick in the case. Listen, you know how I've suspected there is a single mastermind behind all the recent attacks? I think whoever attacked City Hall is our suspect. The same markings showed up at the docks and the mill. All this time, they've kept their business to the north. Low priority. The attack on City Hall changes things. They've gone too far, and they know it. If I can figure out who left this, it can lead me directly to whoever's behind it all. The answer is here, staring me in the face. I can feel it! Wait. What are you wearing? That's a government official seal. Why do you... You're one of them now, aren't you? Just like my parents. How could you? Get out.