I continued running along the wall until I found one area where the wall looked... off. I looked at it, and then to the crowbar I recently obtained. I then looked back to the wall, and started beating the wall with it, to which the wall started chipping away, and showed a briefcase behind it. I pulled it out, but then heard voices, so I Jumped down into the railroad, along with the briefcase, and hid there, waiting for the voices to get to me.