The protesters blocked the entrance to the site, delaying people who were in line waiting to get their shots as it led to a long backup of cars. Some in the group of roughly 30 people waived signs with anti-mask and anti-vaccine messages.
"This is completely wrong," said German Jaquez, who drove from his home in La Verne and had been waiting for an hour for his vaccination when the stadium's gates were closed. He said some of the protesters were telling people in line that the coronavirus is not real and that the vaccination is dangerous.
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A post on social media described the demonstration as the "SCAMDEMIC PROTEST/MARCH." It advised participants to "please refrain from wearing Trump/MAGA attire as we want our statement to resonate with the sheeple. No flags but informational signs only."
"This is a sharing information protest and march against everything COVID, Vaccine, PCR Tests, Lockdowns, Masks, Fauci, Gates, Newsom, China, digital tracking, etc."
According to Andrea Garcia with Mayor Eric Garcetti's office, the protest caused a closure of the gates for under an hour before they were reopened. She added that everyone who had an appointment for Saturday would still be able to get vaccinated.
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The site is usually open from 8 a.m. to 8 p.m.
In a tweet, the Los Angeles Police Department said they were aware of the protest and "preliminary reports are that all protesters remained peaceful."
No arrests were made.
A request for comment from the Los Angeles County Department of Public Health was not immediately returned.
DEVELOPING: This story will be updated as more information becomes available. The Associated Press contributed to this report.