There's more news this weekend of gun stores doing better business in the wake of the Newtown shootings.

The New York Times reports that gun stores all over the country can't keep up with the increased demand for firearms. Online retailers are seeing growth too: "On, an Oracle .223 that normally retails for around $650 had been bid up to $1,175 with three days left in the auction."

And Walmart, America's largest gun retailer, said that some models were out of stock and that some stores had low inventory.

This gun buying boom is happening just as Mayors Against Illegal Guns, an advocacy group headed by Michael Bloomberg, found that millions of mental health records are missing from the national database that gun dealers use to run background checks on their buyers.

States were first required to submit these records to the database in the 1990's. But in 1997, the Supreme Court ruled that adding cases to the information bank was optional. Mayors Against Illegal Guns said that 19 states had fewer than 100 records filed.

[Image via AP]