Fiery scenes erupted outside the National Gallery of Victoria on Thursday night where protesters and police clashed before the 70th anniversary dinner of the Institute of Public Affairs.
News Corp chairman Rupert Murdoch was scheduled to give the keynote speech.
Business figures attended the event, including mining magnate Gina Rinehart (pictured) and News Ltd Australian chief Kim Williams. Cardinal George Pell and Opposition Leader Tony Abbott (pictured, inset) also attended.
The speech was delayed after about 40 protesters forced their way into the venue.
Mr Murdoch this week hit out at Labor's policy on foreign workers, labelling discussion of 457 visas as "pretty disgraceful and racist".