He was a Bosnian immigrant who worked at a uniform shop.
Thank you Velveeta.
This article states the shooter worked at Aramark.
http://deseretnews.com/dn/view/0,1249,660195184,00.html
Aramark, Aramark - why did that ring a bell?
Here's why:
Aramark ran the food court on top of 2 World Trade Center as well as concessions and tours of the observation deck. Several of its employees died in the tower.
And Tom Kean who is on the board of Aramark was on the 9/11 panel.
http://www.usatoday.com/news/washington/2002-12-16-kean_x.htm
Strange coincidence...