According to the Sydney Morning Herald, a source said Urban gave the performance of Merry Widow a standing ovation and was joined by Kidman and many members of the audience.
Spies in the audience told the outlet that a man behind the pair was offended by the fact that Kidman and Urban were on their feet and exchanged words. Urban allegedly explained that the standing ovation was a sign of appreciation and didn’t stop clapping.
The man then allegedly swatted Kidman with his program, which resulted in Urban accusing him of assaulting his wife.
The couple was reportedly escorted out by Urban’s security, as well as Kidman’s mother, Janelle Ann Kidman, who was at the event with them, and Opera House security is said to have handled the unidentified man.
Police confirmed to the outlet that they were called to the Opera House the night the argument took place.
"Police have been told a 53-year-old man and a 67-year-old man were both attending the entertainment center when an argument broke out. Officers spoke to both men and no further action was taken," NSW Police stated.
Kidman and Urban were reportedly escorted through the back of house by Lyndon Terracini and took photographs with the star of the show Virgilio Marino.
Reps for Kidman and Urban did not release a statement about the incident.
Traditionally, standing ovations were considered rude at the opera, as it blocked the view of the person behind them. Clapping and cheering were acceptable as long as people did not stand up, but today they are considered less taboo at opera performances.
Kidman and Urban went to the opera after Kidman completed her mandatory self-isolation when she got back from Ireland, where she filmed scenes for Robert Eggers' project with Ethan Hawke and Alexander Skarsgård.