From the Document: "U.S. Customs and Border Protection [CBP] is the nation's largest federal law enforcement agency charged with securing the nation's borders and facilitating international travel and trade. Our top priority is to keep terrorists and their weapons from entering the United States. At the nation's more than 300 ports of entry, CBP officers have a complex mission with broad law enforcement authorities tied to screening all foreign visitors, returning American citizens and imported cargo that enters the U.S. Along the nation's borders, the United States Border Patrol and Air and Marine Operations are the uniformed law enforcement arms of CBP responsible for securing U.S. borders between ports of entry. [...][This document] is a summary of CBP enforcement actions related to inadmissibles, apprehensions, arrests of individuals with criminal convictions and individuals who have been apprehended multiple times crossing the border illegally."
U.S. Customs and Border Protection: https://www.cbp.gov/