On February 2nd, 2008, a man posing as a delivery driver walked into a Lane Bryant clothing store in a Chicago suburb with a gun. 

He ordered the six women inside the store to the back room, where he duct-taped their hands behind their backs and eventually shot all of them.

Despite a massive manhunt involving multiple law enforcement agencies, the shooter remains at large.

What forensic evidence is there… and will it help identify a mass murderer?