"No shit..." John mutters under his breath. Climbing over the wall would be impossible for someone like John. He tries to find ways to climb on the ticket booth. No ladder, no nothing. What was the other suggestion? 

Oh, right. Yelling.

John starts yelling as loud as he could: "Help! I'm trapped in here! What's going on!", repeating those slogans for about a minute or so. Suddenly a man rushes to help him. He's about 20 years old, pretty tall and slim, with short dark hair. "Wha- How did you get in here? This is a contaminated area! Are you hurt? Let me phone 911 for you...", The man says quickly and pulls out his iPhone to call 911.

"No, no, I'm fine..." John says, "Thanks for your help", completely forgetting the option will bring the po-po to his location.