They're telling me to hide behind a wall in the lobby of a campus building – until they can safely bring me in. The baroque clocks of University College London (UCL) have just struck 7pm, and a security guard is frantically telling me that students are moving into another room – the third one this evening – since an angry mob have discovered the safe-space where we're hiding.

Suddenly they get a phone call and I'm rushed into the classroom. I arrive at the new venue where a dozen students are standing in utter shock. The student organiser, Liora, is telling me to stay inside. If the mob sees me, we will be penned in on all sides.

Suddenly, the campus police are shouting: "Everyone, get inside." They struggle to hold the doors closed. The mob has arrived. I hear the drums and the chants. Soon enough, they encircle the room. They bang on windows; they smash against walls. They keep calling my name: "Hen, war criminal!"

The event was arranged by Jewish students with CAMERA – a group committed to combating libel about Israel at university campuses across the world. England was my last stop on an international speaking tour and while my events in America were a huge success, London proved to be different.

In 2014, I was invited to speak at Kings College London by the pro-Israeli student society. Hundreds of students protested against the event, demanding that the administration not allow me to visit the campus. I was called a murderer and even an active participant in "massacres".

It took place amid an intimidating disruption of students from the Palestinian Society who arranged a classic 'walk-out' stunt. As you can see in the video they published, I urged them to stay while they walked out of the room with taped mouths and poorly written signs, protesting me and my country for our very existence.

It have personally witnessed the problems facing Jewish students in the UK and I thought I knew what to expect. During this year's visit, I was supposed to be hosted at UCL but weeks before the event was due to take place, the student union faced massive pressure from the anti-Israel lobby.

Days before the event, the UCLU, the representative body for University College London students, demanded that the event be cancelled. An email to the organisers alleged that they failed to disclose that I 'was involved in a controversial incident at Kings in 2014' – implying that the nature of the prior incident disqualified me from speaking on campus.

This not only stifled free speech, but it rewarded the protesters in 2014. If activists make an event controversial, they can ensure that a speaker is never invited back. UCLU threatened the Jewish students with disciplinary action if they did not cancel the event.

For a university founded by the great liberal Jeremy Bentham, it is ironic to see threats designed to shut down freedom of speech. Thankfully, the university administration stepped in after a complaint from the Jewish community and our talk was permitted to go ahead.

Hen 2
Protesters chanted: 'Intifada, Intifada' outside the event YouTube

It is 7:30pm and I am inside the classroom with about 25 Jewish students, as well as several parents and community members who came to show support.

The shouting from outside doesn't stop: 'Intifada, Intifada!' they scream. Surrounded by hate, I recall when I was almost killed when I was 12-years-old, during the Second Intifada. Traumatic memories are flooding back.

Amid the chants, four students jump through the window. A young Jewish woman screams in terror. What was supposed to be a peaceful talk has now become profoundly threatening, invaded by a violent mob. Security tells the invaders to back down and leave, but the mob refuses.

The young Jewish students are frightened, and I find myself hugging a female student who is experiencing a veritable panic attack. I am frustrated. On the one hand I want to respond and push back at them. But for what good? It would have brought me down to their brutish level.

In my mind, I know that elements of the media will twist this experience – and contend that I, the speaker, was somehow at fault. So I focus on calming the room – and keeping our restraint and dignity amid verbal assault and physical abuse.

In twenty-first century Britain, Jews leaving a room to screams of 'Shame! Shame! Shame!' is utterly horrifying.

Finally, at 7:45 pm, I begin my talk. The activists are furious – and shout even louder. 'Intifada, Intifada, Intifada!' Hateful rap music is being played on a booming sound system. The police are outside; haplessly impotent. They're simply watching on the sidelines.

I am determined to continue, to not let them stop me from speaking.

I relay my story: of my Mizrahi heritage and the Jews who were ethnically cleansed from the Arab Middle East. Indeed, the assault this evening brings to mind the Farhoud pogrom, the violent dispossession against the Jewish population of Baghdad, Iraq, my family, in 1941. I don't let the mob silence me and my family's story.

I tell them of my humanitarian service in COGAT; how I survived a suicide bombing as a child; and, as a gay man, of my work with LGBTQ civil society in Israel. I struggle to speak above the noise of the protesters – but more than ever, of the thousands of talks I've given across the world, I pour out my soul.

I finish my talk – and reassure the crowd that I would be glad to return. I will not be silenced - and they should not be silenced.

'We won tonight,' I tell them. I ask everyone to be proud of themselves and to stand tall. There isn't a more admirable, more noble cause to support than Zionism, a movement that brought safety to the Jewish people who for centuries experienced oppression and humiliation as a minority across the world.

We all stand up – and we start singing Hatikva, 'The Hope,' Israel's national anthem. We sing higher than the voices of the mob outside. At that moment, even in the face of violence, the music somehow gives us a sense of transcendent safety – and we feel proud.

I am soon rushed out of the campus, in a police coat by the police. They keep telling me: 'don't look back, keep running.' It is if I am escaping a war-zone.

Caracal Battalion
Hen Mazzig served in the Israeli Defence Forces Ilia Yefimovich/ Getty Images

That night strengthened my resolve more than ever. The hateful mob reaffirmed my conviction that anti-Semitism remains alive – in Europe, North American and beyond.

In twenty-first century Britain, Jews leaving a room to screams of 'Shame! Shame! Shame!' is utterly horrifying.

I couldn't sleep all night – I kept on thinking, how do we fight such hate speech? The answer: with good speech. You fight bigotry and fanaticism by standing tall, even when you're afraid. We will continue spreading a message of hope – just as Israel does within the darkness of the Middle East.

Hen Mazzig is a writer, international speaker, social media activist and advocate for his country. He shares his story with campuses and Jewish communities alike, speaking to thousands of people around the world.