"We have signs on the door. We have signs everywhere, but he got very aggressive," said the 7-Eleven manager Juan Martin.
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According to Martin, the man was blocking other customers from paying, pushed the plastic protective shield above the counter and made racist remarks towards the employees.
"The guy said 'I'm an American citizen and I can do in my country whatever I want.' The lady that was working was Hispanic," said Martin.
At least four similar incidents have been reported in Los Angeles. On May 1, a fight broke out inside a Target after several customers refused to wear facial coverings.
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"One of the security guards fell to the ground and then the suspect was on top of him and he sustained a broken arm. Both suspects fled the location and they were recently arrested over the weekend," said Lt. Jim Gavin with the Los Angeles Police Department.
LAPD has categorized this as a "disturbing trend that's happening nationwide."
In the Oakland case, the customer broke the glass door as he walked out.
"He left the store and didn't buy anything and broke the window," said Martin.
Oakland Police tells ABC7 News they're following up on this incident.
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