WASHINGTON - The number of federal background checks for firearms sales declined last month as retailers ran out of guns to sell during a buying spree driven by Washington's new focus on gun control.

Background checks decreased 10 percent nationally between December and January, with large declines in Alabama, Arkansas, Louisiana, Mississippi, Tennessee, Texas and Virginia.

Firearms sales surged throughout the country after the December massacre in Newtown, Conn., that killed 20 children and six adult school workers.

There were more than 2.78 million background checks in December. That was a 12-month peak following an upward trend through last fall. The number fell to 2.48 million in January, still a higher figure than any other month than December last year.

"You can't do a background check if a guy doesn't have a gun to buy," said Mike Fotia, manager of Duke's Sport Shop in New Castle, Pa. "There's nothing to buy."

Gun sales traditionally dip after the rush of the holiday season, and the decrease this year is the smallest since 1998, when the federal government began tracking federally mandated National Instant Criminal Background Checks.

"Availability has been an issue. You're just not able to sell as much," said Katie Stulce, who owns Champion Firearms Corp. in College Station, Texas. "We're probably turning away 60 percent of the people coming in wanting to buy something."

Louisiana, Alabama and Mississippi saw the largest declines in background checks from December to January, by nearly one-third. Those states also saw some of the highest increases in background checks between November and December last year.

Even before the Newtown massacre and White House pledges to curb gun violence with new laws, the gun industry was experiencing a boom in sales. Manufacturers couldn't keep up with demand. After Newtown, gun sales went up even more. People in the gun business called the rush to buy guns after the Newtown shooting a "banic," meaning people are panicked President Obama would ban guns, said Bill Bernstein, owner of the East Side Gun Shop in Nashville, Tenn.