35 ILCS 200/20-110
The amount due for general taxes on property previously forfeited to the State or otherwise remaining unpaid prior to the issuance of the collector's warrant, shall, except as otherwise provided in Section 18-250, be added to the tax of the current year; and the amount thereof shall be charged to the county collector with the amount of taxes for the current year. The amount so charged shall be placed on the tax books, and, except as otherwise provided in Section 21-375, shall be collected and paid over in like manner as other taxes. The county collector is authorized to advertise and sell the property in the manner required by this Code, as if said property had never been forfeited to the State. The county, city, village, incorporated town or school district may, by their agent attend the sale for taxes and buy the property and acquire the same rights that individuals now have under the law, and acquire, hold, sell and dispose of title thereto, the same as and in the same manner as individuals may do under the laws of this State, in case of sale for taxes. The additions and sales shall be continued from year to year until the taxes on the property are paid, by sale or otherwise.
35 ILCS 200/20-110