If the director of a facility in which a person is hospitalized certifies that a person in the custody of the Bureau of Prisons whose sentence is about to expire, or who has been committed to the custody of the Attorney General pursuant to section 4241(d), or against whom all criminal charges have been dismissed solely for reasons related to the mental condition of the person, is presently suffering from a mental disease or defect as a result of which his release would create a substantial risk of bodily injury to another person or serious damage to property of another, and that suitable arrangements for State custody and care of the person are not available, he shall transmit the certificate to the clerk of the court for the district in which the person is confined. The clerk shall send a copy of the certificate to the person, and to the attorney for the Government, and, if the person was committed pursuant to section 4241(d), to the clerk of the court that ordered the commitment. The court shall order a hearing to determine whether the person is presently suffering from a mental disease or defect as a result of which his release would create a substantial risk of bodily injury to another person or serious damage to property of another. A certificate filed under this subsection shall stay the release of the person pending completion of procedures contained in this section.