At about 2:30 p.m., Livermore police officers were called to East Bay Firearms on First Street, where they found a 28-year-old Redwood City man who had been shot at least one time and soon died at the scene.
The man was wearing a mask, a hooded sweatshirt and gloves when he allegedly "attempted to rob the gun store by taking a firearm while armed with a hammer," police said in a news release Monday.
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Police said the store owner appears to have acted in self-defense and is not suspected of committing a crime.
Five other people were inside the store at the time but were not injured.
Anyone with information can call the Livermore Police Department's anonymous tip line at (925) 371-4790.
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