Video shows thieves use a hammer to break a display case at a kiosk at Westfield Plaza Bonita on Tuesday before making off with jewelry.

Police say the smash-and-grab robbery happened about 2 p.m. at Code 1 Jewelry at the mall in National City.

Surveillance video of the incident shows two men approaching the kiosk, taking several swings at a display case and shattering the glass before they start snatching jewelry from the case.

According to owners of the family-owned kiosk, the two suspects were seen walking around the mall for several hours leading up the incident.

“The two guys who came and smashed, they had bags already ready and took our trays,” owner Catherine Kim said. “They went straight for our most expensive section, which is chains. They took all of our chains.”

The video, which lasts just seconds, shows a female merchant picking up a chair and lifting it over the display case in an attempt to fend off the two men. They then were seen fleeing the area of the kiosk.

No arrests have been made and no further suspect information was immediately available.

The robbery comes amid a recent series of similar incidents at stores in California and elsewhere where groups of thieves generally are breaking glass and stealing from retail stores. About 20 people were involved in a smash-and-grab last month at a Los Angeles-area Nordstrom store and dozens reportedly took over at least 10 stores in November in San Francisco, including a Louis Vuitton location.

Following high-profile burglaries in Northern California, California Highway Patrol announced its Organized Retail Crime Task Force was ready to assist local law enforcement and San Diego police said ahead of Black Friday that additional officers were being deployed as a deterrent.

Some in the mall Tuesday initially believed the sound of the smashed glass to be gunshots. National City police confirmed to FOX 5 there were no other weapons used other than the hammer.

Roughly $250,000 in jewelry now is reported as missing, Kim said.

Anyone with information on the robbery is asked to call National City police at 619-336-4475 or send in tips anonymously by contacting Crime Stoppers at 888-580-8477.