Thieves temporarily disabled alarm systems and burglarized three restaurants in San Dimas.
Surveillance video from early Sunday morning shows four men breaking into La Villa Kitchen.
The burglars, wearing dark clothing and hoodies, entered the restaurant by smashing through the glass front door and used flashlights to search for valuable items.
The restaurant owners believe the same thieves are responsible for breaking into two other restaurants in the same plaza on Via Verde Avenue: Palermo Bakery and O Sushi & Grill.
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"They knew exactly where to go," said Joseph Durkin, owner of Palermo Bakery. "They went right to the register."
The burglars didn't leave with cash because the registers were empty and the safe was bolted to the floor, the business owners said.
But the burglars temporarily disabled the alarm systems, which didn't go off until Los Angeles County Sheriff's deputies arrived the next morning.
Jerry Ramirez, owner of La Villa Kitchen, said the thieves popped the systems open and unscrewed the communications.
Ramirez's immigrant parents opened the restaurant in 1986. He said his mother died of COVID at the start of the pandemic, and his family business has struggled to survive months of lockdowns.
Now they'll have to invest in new security equipment.
"And now the recession heading here," Ramirez said. "We're having to worry. And burglary - it's a hit after a hit after a hit. Hard to get back up when you feel so knocked down."
Ramirez is especially incensed that the burglars broke the "thank you veterans" banners that hung near the front door of the Mexican restaurant, advertising a monthly classic car show that draws more than 200 people to fundraise for local charities.
"Criminals are disgraceful," Ramirez said. "They have no respect for our United States of America."
While the LA County Sheriff's Department investigates the break-ins, the owners at La Villa Kitchen said they will continue helping the community.
They plan to proceed with the car show fundraiser Friday, which will raise money to help American veterans.