Elected officials in Connecticut want Facebook to take Sandy Hook conspiracy theorist pages down; Facebook says no -- but points out that it has been dealing with the issue and is in constant contact with families affected by the tragedy.

Most vendors at gun shows are federally licensed dealers, who are required to do background checks on buyers. It's gun collectors and private sellers that aren't federally licensed.

This week, Marketplace's Sylvester Monroe reports from Englewood, a neighborhood on Chicago's South Side, which has one of the highest homicide rates in the city.

Gun stores are busy since the school massacre in Newtown, Conn., revived concern about gun laws. Shops like Blue Ridge Arsenal in Virginia are sold out of some models, but are a gathering place for training and target shooting.