A vaccination hub has been forced to close after the team faced disruption from anti-lockdown protesters.
Vaccinations at the mobile site in Hove, East Sussex, had to be paused on Sunday to ensure people could get the jab "safely and without pressure," the local NHS body said.
Footage shared on social media appeared to show protesters chanting as a vaccine bus left Hove Lawns escorted by police.
It comes as surge testing is underway in Brighton and Hove due to a rise in COVID cases in the area.
The NHS Brighton and Hove Clinical Care Group (CCG) said in a statement on Twitter: "We are sorry to announce that there has been a change to vaccination services in the city today.
"Whilst giving people first and second vaccinations at Hove Lawns yesterday, the mobile team experienced disruption during the anti lockdown measures protest in the city."
The CCG said that the service has been postponed on Sunday to "ensure that everyone is able to receive their vaccine safely and without any pressure put upon them."
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They added that a walk in vaccination service will continue to be available at Brighton racecourse until 6.20pm where anyone can attend without an appointment.
Vaccinations will also continue on Monday morning at the Brighton Centre, they added.
"We continue to be fully committed to the roll out of the vaccination programme and ensuring that everyone in the city is able to access their vaccination," The CCG added.
Local council leader Phélim Mac Cafferty said: "As we have rising cases, it is incredibly disappointing to see the irresponsible actions of a few putting in danger the many.
"We reaffirm out city's need to keep our population safe and we won't be deterred from our important vaccination programme by the acts of cowards spreading misinformation."
"We encourage everyone to take up both vaccinations at the earliest point they can.
"Our proud tradition as a city is that we work against adversity and we won't be deterred from fighting the pandemic together."
Yahoo News UK has contacted Sussex Police for comment.
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