Police are examining CCTV footage after a banner announcing a gay culture festival at JW3 was defaced.

Clear pictures were passed to officers by the centre after a man was caught on camera spray painting the word ‘shame’ on a poster about the GayW3 event outside the venue in the early hours of Thursday.

Rather than removing the banner, one staff member suggested adding letters to turn the graffiti into the word ‘unashamed’ – a move that was roundly applauded on social media.

It was the first time the centre had experimented such an act of hate, JW3 chief executive Raymond Simonson wrote in Facebook.

He said: “The good news is that the coward who crept over in the dark of night at 3.55am this morning with his cans of spray paint, failed in the strong winds to do as much damage as he was trying to do. Even better is that we have very clear images from three different security cameras, and that all footage is now with the police, who are taking this as seriously as I am.

“We’ve had dozens of banners outside our building in the past couple of years, promoting “Israel Week”, “Gefiltefest”, “Jewish Book Week”, “Haaretz Conference”, “UK Jewish Film Festival”, “SERET Israeli Film & TV Festival” and more. And none of them have been vandalised or damaged. The first time the word “Gay” goes up, we have our first experience of this kind of hate crime.”

He also revealed that a message being circulated imploring members of the Orthodox community to boycott the centre in protest at the festival.

Simonson called for the series of evens to become the most attended in the centre’s history as a response to those urging a boycott and the graffiti attacker.