Under Section 10(3) of the Act, at any time after the publication of the notification under sub-section (1) thereof, the competent authority may, by notification published in the Official Gazette of the State concerned, declare that the excess vacant land referred to in the notification published under sub-section (1) shall, with effect from the said date as may be specified in the declaration, be deemed to have been acquired by the State Government and upon publication of such declaration, such land shall be deemed to have vested absolutely in the State Government free from all encumbrances with effect from the dates so specified. Under sub-section (5) of Section 10 of the Act, where any barren land is vested in the State Government under subsection (3), the competent authority may, by notice in writing, order any person who may be in possession of it to surrender or deliver possession thereof to the State Government or to any person duly authorised by the State Government in this behalf within 30 days of the service of the notice. Under sub-section (6) thereof, if any person refuses or fails to comply with the order made under sub-section (5), the competent authority may take possession of the vacant land or cause it to be given to the State Government concerned or to any person duly authorised by such State Government in this behalf and may for that purpose use such force as may be