How can someone stop an ex move out of state with children when it is stated in court papers that neither.....

parent is to move out of state. The parent that has sole custody told the parent with visitation today that when they get income tax back they will be moving several states away. Is there any action that can be taken now to nsure that the parent does not take off with the children? Any help would be appreciated. Both parents live in the state of Ohio the custodial parent is planning on moving to Georgia. HELP!!!!!!!!!!!