These days its extra hard to get control of this behavior. Parents are not willing to see their child as a bully. It becomes a real he said/she said and often no winners. Then, the bullied child is worse off. When my son was beat up and told me he was having some older boys go after the kid I said "good for you". Honestly, I knew this bullies parents and I would get nowhere with them. My son was a small. skinny, kid. Desperate times call for desperate measures.
Two of my daughters got in fist fights at school. They didn't get in trouble. That was in the 90's. They didn't get picked on anymore either. Like Shefali says, I don't condone hitting or punching but if its the only way, it beats the alternative...a child with such low self esteem they take their own young life.