In all cases in which any person has heretofore entered upon and occupied or shall hereafter enter upon and occupy, any lands, tenements or hereditaments within this state, by virtue of any lease or permit from the United States or this state, such person, his, her or their legatees, executors, administrators, heirs or assigns, may have and maintain an action of ejectment against any person who has or may enter upon such lands, tenements or hereditaments without the consent of such lessee, his, her or their legatees, executors, administrators, heirs or assigns, and proof of the right of possession shall be sufficient to authorize a recovery.
735 ILCS 5/6-103