(CNN)A controversial advertisement projected on the side of the Sydney Opera House was disrupted by a sea of lights on Tuesday evening, as protesters attempted to ruin the light show with flashlights and smartphones.
Sydney Opera House protesters disrupt horse racing advertisement
Plans to splash an advertisement for the Everest Cup horse race on the side of the UNESCO World Heritage site fiercely divided Australia's largest city in the past week.
While some considered the use of an Australian cultural icon to promote a race "sacrilegious," Prime Minister Scott Morrison said it was logical to use the "biggest billboard Sydney has."
Hundreds of protestors shouting "our house" gathered outside the Opera House late on Tuesday, carrying banners and torches ahead of the light show which began shortly before 8 p.m. (5 a.m. ET).
Loud boos broke out when the side of the building lit up with the advertisement for the upcoming race and bright white lights from the protestors' flashlights partially disrupted the light show.
The controversy began on Friday when media in Sydney announced the Opera House had refused a Racing NSW request to advertise the upcoming horse race on the side of the historic building.
The annual Everest Cup horse race is being held for only the second time and has the largest prize pool for a "turf race" in Australia, coming in at $9.2 million (A$13 million).
New South Wales Premier Gladys Berejiklian claimed the previous year's race attracted 60 million viewers, but the Opera House committee was concerned projecting the ad could cost the building its World Heritage status.
Eventually Berejiklian ordered the Opera House to comply and the advertisement was scheduled to go ahead, saying it would be much "toned down" on the original proposal.
Almost 300,000 Australians signed a petition calling on the NSW government to cancel the light show.