28 USC § 2461. Mode of recovery
(a) Whenever a civil fine, penalty or pecuniary forfeiture is prescribed for the violation of an Act of Congress without specifying the mode of recovery or enforcement thereof, it may be recovered in a civil action.
(b) Unless otherwise provided by Act of Congress, whenever a forfeiture of property is prescribed as a penalty for violation of an Act of Congress and the seizure takes place on the high seas or on navigable waters within the admiralty and maritime jurisdiction of the United States, such forfeiture may be enforced by libel in admiralty but in cases of seizures on land the forfeiture may be enforced by a proceeding by libel which shall conform as near as may be to proceedings in admiralty.
(c) If a person is charged in a criminal case with a violation of an Act of Congress for which the civil or criminal forfeiture of property is authorized, the Government may include notice of the forfeiture in the indictment or information pursuant to the Federal Rules of Criminal Procedure. If the defendant is convicted of the offense giving rise to the forfeiture, the court shall order the forfeiture of the property as part of the sentence in the criminal case pursuant to the Federal Rules of Criminal Procedure and section 3554 of title 18, United States Code. The procedures in section 413 of the Controlled Substances Act (21 U.S.C. 853) apply to all stages of a criminal forfeiture proceeding, except that subsection (d) of such section applies only in cases in which the defendant is convicted of a violation of such Act.