Joyce, the head of Australia's flag carrier, had begun the keynote address on stage at the event when an elderly man in a business suit walked up behind him and pushed what looked like lemon meringue pie into Joyce's face. The man, aged in his late 60s or early 70s, then walked calmly off the stage towards an exit.
The Qantas CEO was at first stunned by the incident, but quickly regained his composure and told the audience of more than 500 people, "I don't know what that was about" before excusing himself to "clean up."
He then returned to continue his speech, without his jacket.
Talking to reporters later, Joyce joked that he had been not been able to identify what flavor the pie was.
"I didn't have a chance to test it, it was mostly on my glasses. I think my issue is I need a good dry cleaner before I leave Perth," Joyce said.
The unidentified man was arrested by security staff and is being interviewed by police. He was expected to undergo a mental health assessment and possibly be charged with assault.
Last week, Qantas reported a decline in revenue for the third quarter, but confirmed that it expects to report a full-year underlying profit that would represent the second highest result in the carrier's history.
(RTTNews / Business Insider)