Cases like these, some people just spook and took off. It is a natural reaction or habit to keep on driving? I dunno.
Why flea to thailand? The conscious is one heck of a drug. Egor Allen poe, the famous writer once wrote a short story about it. This is why some criminals end up turning themselves in. The unknown, unthinkable is too unbearable to face. Every sound, every siren, you be thinking that the cops are coming after you. You don't even know if the person you hit lives or die. You know that these days, there are camera on street corners and cameras at gas station to see you zooming on by. When you hit someone or something, there are evidences from your car is left behind. Lose a side mirror or head lights? I can figure out which model and color your car is. Your mind keeps on playing tricks with you. You can even hear your heart beat pounding on any silence and it is tormenting you.
Almost sounds like I have previous experiences huh?