A senior mental health lecturer who allegedly called a remain campaigner a “fucking traitor” and brandished a union jack flag in his face is being investigated by King’s College London.

In a video shared on Twitter, Niall McCrae also appears to tell Femi Oluwole to “fuck off” at the Brexit party rally in west London on Tuesday.

McCrae is then seen waving a large union jack flagpole in the campaigner’s direction and later shakes the hand of a man who had thrown water at him.

A King’s College London spokesperson said: “We are aware of complaints regarding the conduct of a member of our staff. We do not condone inappropriate or abusive behaviour. This is being taken very seriously and is being dealt with as a priority.”

McCrae, who has been a lecturer at King’s mental health nursing department for 17 years, writes about Brexit for rightwing thinktank the Bruges Group and has written academic papers researching the impact of Brexit on the health service.

He campaigned to leave the EU in Sutton, south London, an area which voted for Brexit.

Oluwole had been carrying a desk with a sign reading: “A no-deal Brexit would be disastrous for the UK. Change my mind,” next to people queueing for the rally.

He later shared the footage of the incident on Twitter, adding: “I don’t mind rightwing thugs chucking their drinks on me. I don’t mind them poking me in the face with a flagpole.

“I do mind that Nigel Farage is set to WIN the European elections on Thursday, by calling anyone who opposes a form of Brexit he said would never happen ‘traitors’.”

Oluwole co-founded Our Future Our Choice, a campaign group for young people who want a second referendum.

McCrae has been contacted for comment.