Anti-fascist protesters heckled and abused blood donors after mistaking them for supporters of a political party.
The National Blood Service was taking donations from residents at Hove Town Hall on Monday evening – the same night UKIP leader Nigel Farage was also set to give a speech to crowds inside the hall.
Anti-fascist protesters, who opposed the party’s policies, gathered with banners and placards outside the venue prior to Mr Farage’s talk at 7pm.
But they mistakenly identified blood donors who entered the building as UKIP supporters and hurled abuse at them.
Eileen Meehan, 67, from Brighton, described the experience as shocking and intimidating.
She said: “I’ve given blood many times before over the years but I’ve never experienced anything like Monday night.
“There was a big crowd of angry people with banners and I thought we’d be ok as it was going on for something else.
“But as I walked through the front entrance I was called a racist and was told I had no shame.
“So many people were abused for doing a good thing. It was disgusting.”
Another donor, who wanted to remain anonymous, said: “They should be ashamed of themselves.
"Why don’t they get themselves down to the next available donation service to make up for it?
“People who give blood shouldn’t put up with that nonsense.”
A spokeswoman from the National Blood Service confirmed some donors reported abuse on Monday night.
She said: “A small number of donors reported being heckled by protesters as they entered the building.
“However, the donors were able to come in and make their donation and leave safely.
“We are not aware of donors who felt unable to continue into the building to make their donation and the blood donor session was able to run until the planned finish time of 8pm.”