Border Patrol agent shoots and kills driver who tried to flee into Mexico

NOGALES, AZ (NBC) - A port of entry along the southern border has been shut down after a Border Patrol officer shot and killed a driver.

The mayor of Nogales, Arizona said the officer opened fire after the driver of a truck came barreling toward him and refused to stop.

The truck's momentum carried it over the border into Mexico.

Mexican border officials surrounded the truck and discovered the driver was dead, and arrested a passenger.

An investigation is underway.