A person commits the crime of arson if they intentionally damage valuable property by using fire or explosives.  Arson laws typically only apply when the property damaged either belongs to another person, or is insured and was destroyed to defraud the insurance company.  Most states also have an aggravated arson statute to increase the penalty for individuals who commit arson on a building when the person knows, or should know, that the building is occupied by another person, and the fire causes that person severe injury.  These statutes also often apply when a person commits arson and the resulting fire or explosion injures a fireman or policeman responding to the fire.