LifeinAsia - 11:31 pm on Jan 16, 2013 (gmt 0)

In his next email he then told me he was an attorney

It might be fueling the fire, but you could look into filing a complaint with the bar association (or whatever organization has local authority over lawyers) about his behavior. Include copies of all the threatening e-mails/letters he has sent you.

Your case may not be an isolated incident for this person.