Illinois Statutes Chapter 65. Municipalities § 5/7-4-3. Surrounded territory

§ 7-4-3. Whenever, as a result of the annexation of the whole of a municipality to another municipality with a population of more than 200,000, unincorporated territory, not a part of either of these municipalities, has been wholly surrounded by the enlarged municipality, the jurisdiction of the enlarged municipality shall extend over the unincorporated territory so surrounded to the same extent as if that territory had been annexed at the same time as the municipality whose annexation caused the territory to be so surrounded.