Video from the scene shows masked people streaming out of the store, carrying bags and boxes, jumping into the cars and speeding away.
Brett Barrette, the manager of a nearby PF Chang's restaurant, began locking doors at his establishment while watching the chaos unfold.
"We probably saw 50 to 80 people in ski masks, crowbars, a bunch of weapons," Barrette told ABC 7 News.
The Walnut Creek Police Department said a firearm was recovered from one of the three arrested suspects, ABC 7 reported.
The incident was first reported around 8.45pm while the store was still open. Police officials couldn't immediately be reached Sunday morning, but a dispatcher said the department was preparing a news release.
No injuries were reported. Nobody answered the phone at the Nordstrom Sunday morning.
The incident came a day after several high-end stores in San Francisco's Union Square were broken into by a large group of people who smashed windows, stole merchandise, and then ran to waiting cars, police said.
Louis Vuitton, Fendi, Yves Saint Laurent, Burberry, and Dolce & Gabbana were all targeted Friday night, Fox 2 News reported.
San Francisco Police Officer Robert Rueca said in a statement posted on social media that officers responded to reports of possible looting and vandalism at Union Square stores Friday night and arrested several people.
Stores in Union Square, a posh shopping district popular with tourists, have been targeted for years by well-organised thieves who at times have rammed vehicles into storefronts to break glass doors and windows and enter the buildings during non-business hours.
In July, Governor Gavin Newsom signed a law that allows prosecutors to charge those who work with others to steal merchandise.
- AP
