Why is FTX CEO in jail?

I'm quite puzzled why the FTX CEO is currently incarcerated. Given his position at the helm of a multibillion-dollar cryptocurrency exchange, I assumed he enjoyed a certain level of privilege and immunity. Could you please explain the circumstances that led to his arrest and incarceration? Was it due to some illegal activities on his part, or was it a result of some larger scheme within the cryptocurrency industry? I'm really interested in understanding the details behind this surprising turn of events.