Jayda Fransen, who is standing as an independent in Glasgow Southside, the same constituency contested by Ms Sturgeon, confronted the Scottish National Party (SNP) leader outside what appeared to be a polling station, footage posted online showed.
Fransen, who has convictions for religiously-aggravated harassment, accused the first minister of being an “absolute disgrace” for “flooding the country” with immigrants.
She can be heard saying: “What are you sorry for? Mass immigration, Marxism? I'm not a fascist. I've been on the ground speaking to locals who say you are an absolute disgrace...”
Ms Sturgeon responds: “We'll see what the locals' view is later on.”
Fransen says: "The locals, what, the ones you have flooded from other countries?
“The decent people of Scotland don't want it flooded with immigrants.”
Ms Sturgeon tells her: “You are a fascist, you are a racist and the southside of Glasgow will reject you.”
The first minister then walks away with party members as Fransen pursues her, talking about “mass immigration” and “Marxism”.
Fransen later tells an SNP supporter who asks her who she is: “I'm not fascist, just a normal, decent unionist patriot. My grandfather fought the Nazis.”
In a piece to camera uploaded by the British Freedom Party, she accuses Ms Sturgeon of “running away like a coward”, adding: “Of course if you flood a constituency with foreigners and hardline republicans who absolutely hate Britain, hate the union, they are going to secure their votes.
“The unionist community are no longer unrepresented and we are coming for you.”
The first minister later shared footage of the incident on Twitter.
“Glasgow Southside is the most diverse and multi-cultural constituency in Scotland - one of the many things that makes it so brilliant. I am confident it will unite today to utterly reject these fascists,” she wrote.
Fransen has previously been pictured outside the constituency office of justice secretary Humza Yousaf holding a sign saying “it's okay to be white” and has said she is running against the “SNP commie, Marxists, naughty people”.
She has previously been convicted of a number of religiously-aggravated crimes, including harassment in both 2016 and 2018 – the latter of which saw her sentenced to 36 weeks in prison.
Although a member of the British Freedom Party, documents from Glasgow City Council show Fransen is running as an independent.
Additional reporting by PA
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