Controversy continues to plague The Everest horse race, with Racing NSW now suspending all bets on the event – billed as the “world's richest race on turf” – until this evening citing “security risks”.

The original plan was to conduct the barrier draw live and simultaneously project it onto the facade of the Sydney Opera House tonight, but the racing body has brought the draw forward, with the results to be “held in confidence” until the six-minute projection.

In an official statement, Racing NSW said: “[We have] made the decision to conduct the draw prior to the event to circumvent any security risks that may exist.”

An anticipated 3400 people are expected to converge on Bennelong Point from 8pm to stage a “light-based protest” against the projections – a further 16,000 have confirmed their interest in attending. Participants are encouraged to use light sources, such as torches and smartphones, to disrupt the advertising images.

The protest is in response to the NSW government’s decision to override an earlier ruling by the chief executive of the Opera House, Louise Herron, who did not want to project horse names and branding on the building’s sails.

Racing NSW says bets have been suspended “to avoid any perceived integrity risk”, with waging operators to be informed later this evening when they can recommence betting on the annual racing event.

It’s the latest development in The Everest promotion scandal. In the early hours of this morning, comedy group The Chaser projected 2GB radio broadcaster Alan Jones’s phone number onto the Opera House.

Jones publicly apologised to Herron today for his on-air remarks while interviewing her on his breakfast program on Friday. The interview, in which Jones called for Herron to be fired if she continued to deny the promotion of the race on the heritage-listed landmark, has been widely condemned.