Corruption hit by Chinese government to send a message?
They are all corrupt. The current leader's family is reputed to be worth hundreds of millions. Everyone up and down the line gets a slice in order to keep his mouth shut. Anyone who doesn't take a piece of the action is hounded out or dismissed on some flimsy pretext. A possibility is that the guy who was killed with his family was applying for refugee (and witness protection) status stateside in exchange for telling all, and the Chinese state security apparatus intercepted his phone calls and/or e-mail.