Protesters briefly disrupted a coronavirus vaccination distribution center at Dodger Stadium in Los Angeles, US media reported Saturday.
Several dozen people carrying signs demanding the end of lockdowns and promoting anti-vaccination conspiracy theories gathered at the entrance to the site, one of the largest in the US, social media posts showed.
"There appears to be only about 30 protestors total. It's not clear why they’ve shut off the whole facility," tweeted social media user Mikel Jollet.
Officials shut the site down for nearly an hour, US media reported, citing fire department officials -- though the Los Angeles police department later insisted that the site had not been shut down and that all the vaccines would be distributed.
The incident represents just the latest challenge to the vaccine rollout in the US, which has the highest number of cases and deaths in the world from Covid-19.
More than 26 million people have been infected and 439,000 have died in the country since the start of the pandemic, a tally kept by Johns Hopkins University showed Satuday.
President Joe Biden has pledged to have 100 million people vaccinated within his first 100 days -- but the rollout began slowly under former President Donald Trump.
Los Angeles county, where Covid-19 cases have surged this winter, is currently only vaccinating frontline medical workers and people aged 65 and over.
Even among those groups, appointments are extremely difficult to obtain, with Pfizer-BioNTech and Moderna shots in limited supply.