It happened during the performance of “Seek And Destroy,” in Sydney, Australia with the house lights on and the stage filled with huge black balloons.
Guitarist Kirk Hammett wandered through the crowded stage, kicking balloons at random; at one point, he unknowingly kicks a small child while following through on one of the balloons.
The child is seen to be thrown backwards in the air, landing in the crowd.
It’s unclear, from the audience-shot footage, if Hammett kicked the child directly, or if the youth was simply thrown by the guitarist’s foot connecting with the balloon.
Following the kick, a roadie can be seen rushing the child across the stage, presumably headed somewhere for further attention.