19 C.F.R. § 4.3a
Violation of the arrival or entry reporting requirements provided for in this part may result in the master being liable for certain civil and criminal penalties, as provided under 19 U.S.C. 1436 , in addition to other penalties applicable under other provisions of law. The penalties include civil monetary penalties for failure to report arrival or make entry, and any conveyance used in connection with any such violation is subject to seizure and forfeiture. Further, if any merchandise (other than sea stores or the equivalent for conveyances other than a vessel) is involved in the failure to report arrival or entry, additional penalties equal to the value of merchandise may be imposed, and the merchandise may be seized and forfeited unless properly entered by the importer or consignee. The criminal penalties, applicable upon conviction, include fines and imprisonment if the master intentionally commits any violation of these reporting and entry requirements or if prohibited merchandise is involved in the failure to report arrival or make entry.
19 C.F.R. §4.3a