This afternoon in Melbourne, refugee activists protesting against the Australian government's offshore detention policies stormed the stage as Prime Minister Malcolm Turnbull gave a major economic address.
It's just as well that this incident has prompted a security review. This review needs to establish how these protesters were able to pass security checks. They were only carrying signs and shouted angry slogans, but they could easily have been carrying weapons.
This comes only a few days after a Victorian state MP was assaulted on an inner-city street.
One hopes that political violence doesn't become a permanent part of Australian political culture, from either the left or the right.