Cellphone video obtained by ABC7 Eyewitness News shows suspects using hammers to break into Zales Jewelers at Stoneridge Shopping Center in Pleasanton. The robbery happened around 11:30 a.m., according to police radio traffic.
For employees working elsewhere in the mall, the day quickly became chaotic.
"We have a restroom over there and I was hiding in that hallway," said Tina Deng, who works at Yuyake Dandan Japanese Tapas.
Deng said she heard the theft unfolding nearby.
"They were smashing the glass," she said. "It sounds like gunshots but not that loud."
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Deng and her coworkers were not injured, but she said everyone was shaken by the incident.
"Surprised for sure and scared for sure because I don't know if those people have guns or what kinds of weapons," Deng said. "I could hear them running, their footsteps too."
Police radio descriptions indicated the suspects used hammers and pepper spray during the robbery.
Pleasanton police have not commented on the incident and have not said whether any arrests have been made.
ABC7 Eyewitness News saw two jewelry cases that appeared to have been emptied.
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Scott Guginsky of the Jewelers' Security Alliance said rising precious metal prices have made jewelry stores more attractive targets.
"The prices of precious metals are very concerning," Guginsky said. "You know, we had gold peaking at $5,200 an ounce and I believe today it might have closed at 4,600 an ounce. So, a lot of these stores, that carry 22, 24 carat gold are being targeted, because of the value of the precious metals."
Guginsky said new research from his organization shows thieves are changing tactics during these crimes.
"In 2024, with these types of robberies, we had three cases where they utilized mace, and we had 14 last year," he said.
Guginsky recommended armed security as a deterrent and said law enforcement has tracked down many suspects in similar cases.
Several shoppers told ABC7 Eyewitness News they were concerned about safety and security at the mall following the robbery.