Dramatic scenes in Brussels today at the National Conservatism conference offered a harrowing harbinger of what a police state in the heart of Europe might look like.

After the conference began, local Brussels police suddenly arrived at the Claridge building hosting the conference, and proceeded to set up a barricades in front of the event venue, preventing any further attendees, journalists or speakers from accessing the event, reports local media Brussels Signal.

Eric Zemmous, the French politician, who was due to appear at the conference but was barred from entering when he turned up, said the city’s left-wing mayor had deployed the police like a “private militia” to stop a conservative conference from happening in Brussels.