This is allegedly an attack on the Australian Treasury by people not happy with the latter’s neo-liberal policies. (Hat tip to Billyblog.) My only criticism is that the balloonists didn’t fill the balloons with an approximately 50:50 mixture of hydrogen and oxygen. That would have been lighter than air, plus when ignited it would have blown the Treasury windows out.
It would probably have killed the balloonists, but then many of us are making sacrifices at the moment with a view to getting more sensible economic policies in place.