The United States Immigration and Customs Enforcement (ICE; ) is a federal law enforcement agency under the U.S. Department of Homeland Security. ICE's stated mission is to protect the United States from transnational crime and illegal immigration that threaten national security and public safety. ICE enforces over 400 federal statutes, focusing on customs violations, immigration enforcement, terrorism prevention, and trafficking. ICE has two primary and distinct law enforcement components, Homeland Security Investigations (HSI) and Enforcement and Removal Operations (ERO), in addition to three supporting divisions: Management & Program Administration, Office of Principal Legal Advisor (OPLA) and Office of Professional Responsibility (OPR). HSI is focused on the disruption of transnational crime, whereas ERO is responsible for the apprehension, detention and removal of undocumented immigrants.