8 C.F.R. § 280.2
In any case in which the imposition of a fine is predicated upon an alleged violation of a regulation promulgated under authority of section 239 of the Immigration and Nationality Act, the procedure prescribed in this part shall be followed and the aircraft involved shall not be granted clearance pending determination of the question of liability to the payment of any fine, or while the fine remains unpaid; but clearance may be granted prior to the determination of such question upon the deposit of a sum sufficient to cover such fine or of a bond with sufficient surety to secure the payment thereof, approved by the Commissioner. If the alleged violation was by the owner or person in command of the aircraft, the penalty provided for shall be a lien against the aircraft, which, except as provided in § 280.21 , shall be seized by the district director or by an immigration officer designated by the district director, and placed in the custody of the customs officer who is in charge of the port of entry or customs station nearest the place of seizure. If the owner or owners of the airport at which such aircraft is located are the owners of the seized aircraft, the aircraft shall be removed to another suitable place for storage if practicable.
8 C.F.R. §280.2