This from Mayor Michael Bloomberg:

“Omar Samaha, a Virginia Tech graduate, who attended the event and whose sister Reema was among the victims of the shooting, recently purchased ten weapons at a Virginia gun show with no background check performed.  The weapons he purchased without a background check include a Glock similar to the one that killed his sister.

Although federal law requires gun dealers to conduct background check on people purchasing weapons, it exempts so-called “occasional sellers,” who often conduct business at gun shows.  The loophole provides criminals with easy access to firearms without having to worry about any background checks.

A study released in December 2008 by the Mayors Against Illegal Guns coalition, which Mayor Bloomberg co-chairs, showed guns recovered in crimes across state lines were more likely to come from Virginia than all but five other states.  The report also showed that states that have yet to close the gun show loophole are sources of guns used in crimes in other states at more than twice the rate of states that require background checks for all sales at gun shows.

An April 2008 bi-partisan poll conducted jointly by Greenberg Quinlan Rosner Research and the Tarrance Group and commissioned by Mayors Against Illegal Guns found that 87 percent of Americans and 83 percent of gun-owners support requiring background checks for all sales at gun shows.”