Trans rights protesters have interrupted a talk given at the Oxford Union by a feminist who campaigns for women's single sex spaces.
One demonstrator glued their hand to the floor in front of "gender-critical" academic Professor Kathleen Stock, leading to an interruption lasting almost half an hour.
Four police officers spent about 10 minutes attempting to remove the activist as security asked those in the audience not to record or take pictures of the incident.
Two other protesters emerged waving rainbow flags and throwing leaflets, before being drowned out by the crowd and removed by security.
One audience member told them "we are here to listen" to (Prof Stock) whether they "like it or not".
The former philosophy lecturer, who is a lesbian, resigned from Sussex University in October 2021 after being accused of transphobia - an allegation she strenuously denies.
The person who glued themselves to the floor, Rizz Possnett, who describes themselves as "trans" on their Twitter bio, with "they/them" pronouns, tweeted afterwards: "Kathleen Stock is not welcome here.
"TERFs (trans-exclusionary radical feminists) are not welcome here. We will resist hatred, and we will fight for trans rights."
But they added: "Whilst I believe her speech is dangerous and hateful, she is entitled to exercise her right to free speech."
During her talk, Prof Stock argued that trans women - born male - should not be able to access female-only spaces.
When those born male are removed from such spaces it is "on the assumption that some males are predators", she said.
Prof Stock continued: "We are not doing that as a society. We are supposed to care about women. It is (the) risk of a man saying he is a woman and going into a space and taking advantage of that."
When pressed by the union's president, Matthew Dick, on whether trans women posed a similar risk to biological men in general, Prof Stock cited statistics by the Ministry of Justice which show that "at least 50%" of those in prison are there for sexual assault, adding: "That's a higher rate than the average male."
She added: "The people outside totally misunderstand what I'm saying but somebody has to say it."
Earlier, about 200 protesters gathered at Oxford's Bonn Square before marching towards the 200-year-old debating society, prior to Prof Stock's arrival.
Speaking at the rally, Max Van Kleek, associate professor of human-computer interaction at the university, said transgender students suffered "so much abuse" and were "losing rights around the world".
"Let us all unite in trans solidarity and show people we are not something to fear," he said.
On banners were messages including "Trans Rights Now" and "Our Existence Is Not A Debate".
There were also a number of counter-protesters.
There has been a row over whether Prof Stock should appear at all, with the university's LGBTQ+ society calling for her invitation to be rescinded, describing her as "transphobic and trans-exclusionary".
But the university's vice-chancellor, Professor Irene Tracey, has said her appearance is a matter of "freedom of speech".
And Rishi Sunak, the prime minister, said a "free society requires free debate" and people should be "encouraged to engage respectfully with the ideas of others".