Miss. Code Ann. § 3-5-7: Miss. Code Ann. § 3-5-7

So long as the lands acquired by the United States pursuant to Sections 3-5-1 and 3-5-3 shall remain the property of the United States, and no longer, the same shall be exempt from all state, county and municipal taxation, assessment, or other charges which may be levied or imposed under authority of the state.