I've already seen him twice. He's always staring at people strangely and insistently, with a threatening air. This guy has an obvious mental problem. Now the question to ask from an immigration point of view is how this person managed to come and, moreover, to stay here. When we know all the hassles imposed on regular tourists (forms to fill out, proof of stay, budget and others), we can ask ourselves questions. Apparently the authorities have already interrogated him. Why didn't they send him back if he doesn't respect the conditions of stay in Thailand?