No demand for the extradition of a person charged with crime in another state shall be recognized by the Governor unless in writing and accompanied by a copy of an indictment found, or by an information supported by affidavit, in the state having jurisdiction of the crime or by a copy of an affidavit made before a magistrate there, together with a copy of any warrant which was issued thereon. The indictment, information or affidavit made before the magistrate must substantially charge the person demanded with having committed a crime under the law of that state, and the copy must be authenticated by the executive authority making the demand, which shall be prima facie evidence of its truth.