California has seen a surge in gun sales in recent months, with background checks hitting new highs, continuing trends that began after last year's terrorist attack in San Bernardino.

KPCC obtained data on firearms sales from the California Department of Justice, which tracks them through a system known as the Dealer's Record of Sale.

As of April 15, the data show more than 44,000 firearms sold in Los Angeles so far this year, and another 21,000 sold in both Orange and Riverside. Nearly 20,000 firearms have been sold in San Bernardino County.

Sales are outpacing last year's, particularly for the Inland Empire counties.

County 2016 gun sales (through Apr. 15) 2015 Gun Sales Los Angeles 44,303 132,376 Orange 21,664 63,393 Riverside 21,435 61,121 San Bernardino 19,956 56,378 Ventura 7,220 22,014

The sales reflect both handguns and long guns, such as rifles. The numbers could all tick up, as there are pending sales in each county.

Local retailers say they saw the surge start after the mass shooting in San Bernardino, in which 17 people were killed.

"Everybody and their mother was coming out and just getting firearms," said Vince Torres, who owns the Bullseye Sport gun store in Riverside.

Business is still above average, Torres said. "But it's not as strong as it was December, January, February and through March." The store's hold message features Torres thanking customers for their patience in recent months.

He said he has no plans to swap out the hold music, which also plays an excerpt from "The Battle Hymn Of The Republic."

Torres attributes the sales bump to the San Bernardino shooting and President Barack Obama's executive order on gun control in January. He said he's trying to keep customers updated on a handful of gun control bills in Sacramento.

Between those bills and rhetoric on gun control in the presidential campaign, Torres predicted, "we're probably going to have a stronger summer than we usually do."

Federal data on background checks reinforces the trends on firearms sales in California.

In December 2015, gun dealers requested background checks on 253,946 potential buyers in California—the first time that number has gone above 200,000 since the FBI started keeping track in 1990. Every month since has seen at least 200,000 requests for background checks.

However, the FBI cautions that background checks are an imperfect measurement of actual sales—not all sales require background checks and not all background checks result in sales.