Metallica guitarist Kirk Hammett proves that balloons and small children don't mix.

According to Rolling Stone, the rocker was kicking balloons around at a show last week when he accidentally hit a kid.  Oops.  Full story below:

Metallica has had onstage mishaps involving pyrotechnics and falling stage props in the past, but you'd have to think balloons would be pretty low on the danger scale. Guess again: During a show in Sydney last week, guitarist Kirk Hammett was kicking balloons around the stage during "Seek and Destroy" and, in this audience-filmed footage from Liveleak, accidentally clobbered a small child as well.

The child is seen being carried away, and reported that despite rumors that the child was the son of frontman James Hetfield, it was apparently the daughter of the group's production or tour manager.

The site also said that the child was reportedly not injured during the incident.