CHAMPAIGN – Background checks for gun sales in Illinois have almost doubled since the school shootings in Connecticut a week ago, according to data from Illinois State Police.

Gun sellers said some buyers appear concerned about self-defense, but many already own guns and appear to be adding to their collections amid talk of tougher restrictions on gun ownership. Semiautomatic rifles like the AR-15 used in the school shootings in Connecticut are generating much of the interest, sellers said. Those guns are being mentioned as the mostly likely target of tougher laws.

More than 12,500 background checks were done in Illinois between Dec. 14, when 28 people were killed in Newtown, Conn., and Tuesday, according to data provided to The Associated Press by state police. In comparison, 6,870 checks were done during the same time a year earlier.