WASHINGTON (AP) - The number of federal background checks for firearm sales declined unexpectedly last month following a surge toward the end of the year as Washington considered new gun control measures.

An Associated Press analysis of new FBI data published early Tuesday shows the National Instant Criminal Background Check system processed more than 2.78 million 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 greater than any other month last year.

The 10 percent drop between December and January comes amid a fierce national debate on gun control after the horrific school shooting in Newtown, Conn.

Louisiana, Alabama and Mississippi saw the largest declines in background checks from December to January, by about one-third.

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