A 10 yr old kid shoots 6 classmates with a BB gun...what is wrong with this picture?

This kid shoots a classmate when the teacher is not looking….she looks away and he hits another….then another. It is not till after class that a student tells the teacher what happened. WTH is wrong with these kids? My biggest question is why did they not say anything while it was happening? Who is to blame here and how should this kid be punished? What is it with Colorado, kids and guns?