Conduct disorder is characterized by a variety of symptoms that typically involve aggression towards people and animals, and serious violation of rules. Such children may deliberately destroy the property of others by either setting them on fire or by other means. Stealing objects, bullying others, and running away from school are also common behaviours shown by such children. Sometimes such children are rejected by children of their age group, but in some cases, they may have friendships which may include other children with behavioural problems.