Those who dropped by the In-N-Out in Livermore Wednesday were greeted by traffic cones blocking the entry to the parking lot.
At trip along Interstate 580 would be incomplete without a stop at the In-N-Out in Livermore.
"We heard a lot about it from our Californian relatives that we should try In-N-Out Burger, so we saw one, and now I'm a bit worried as to why it's closed," said tourist Raymond Kennedy, who is visiting from the United Kingdom.
Wednesday afternoon it was an uncharacteristic scene, customers being told to stay away until further notice.
"This is one of my regular stops on the way to LA and I can eat it in the car and hurry up and get down, so yeah I was shocked," said Velma Horn-Cantrell of American Canyon.
As a precaution, officials made the call to voluntarily close the location on North Livermore Avenue after nine people from a travel group reported feeling sick after recently dining at the restaurant.
In a statement, a company spokesperson said: Our investigation did not turn up any indication that there were any issues at our restaurant. Nonetheless, we thoroughly cleaned and disinfected the entire facility.
Livermore mayor John Marchand applauded In-N-Out for their proactive approach, calling the company a terrific community partner.
"They know how popular this is, so if there's any question in their mind, they want to make sure that no one, no individual's going to be put at risk," Marchand said.
ABC7 News checked with the Alameda County Environmental Health Department website, which shows the restaurant did pass its two most recent inspections but was cited for a food safety violation during a routine check last Dec.
Despite all of this, customers say they'll be back.
"Yes, In-N-Out is one of my favorite restaurants," said Concord resident George Croitor. "Double Double."
In-N-Out says it will reopen the restaurant after the health department completes an assessment.
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