Every foreign mail, while being transported across the territory of the United States under authority of law, is mail of the United States, and any depredation thereon, or offense in respect thereto, shall be punishable as though it were United States mail.
18 U.S.C. § 1692
HISTORICAL AND REVISION NOTES Based on title 18, U.S.C., 1940 ed., §359 (Mar. 4, 1909, ch. 321, §229, 35 Stat. 1134).Minor changes were made in phraseology and obvious surplusage omitted.