Immediately let the person harassing you that the actions/statements are unwanted and then report the incident to your supervisor or company owner. Also, have any witnesses give written statements to you of what they witnessed. Keep a journal of the incidents if there is more than one incident. Keep reporting the incidents.
If the employer or owner does not take effective immediate remedial action against the offender, report the problem to either the state or federal labor commissions. In Oregon, it is the Bureau of Labor and Industries, and the federal government operated the Equal Employment Opportunities Commission. Either one of these entities can take your complaint, investigate it, and provide you with their findings which can help you in the event you decide to sue the offender and/or the company for sexual harassment or for maintaining a hostile work environment.