Whenever two or more persons assemble for the purpose of committing criminal sabotage, as defined in RCW
9.05.060, such an assembly is unlawful, and every person voluntarily and knowingly participating therein by his or her presence, aid, or instigation, is guilty of a class B felony and shall be punished by imprisonment in a state correctional facility for not more than ten years, or by a fine of not more than five thousand dollars, or both.