The number of background checks in the United States for gun purchases set a record in December, as the Connecticut school massacre prompted renewed talk of limits on firearms.
The FBI recorded 2.8 million background checks during the month, surpassing the record set in November of two million checks.
The number was up 49% on the figure for December 2011, when 1.9 million checks were conducted.
December is typically the busiest month of the year for checks, due in part to Christmas gift sales.
The figures do not represent the number of firearms sold.
Persons who pass a background check is eligible to buy multiple firearms.
FBI checks for all of 2012 totaled 19.6 million, an increase of 19% over 2011.
Twenty children and six adults were killed at Sandy Hook Elementary in Newtown, Connecticut, on 14 December.
The killer shot himself at the school. His mother, who was the registered owner of the guns he used, was killed before he went to the school.