Yes they can. also transporting any illegal alien in your car can have it confiscated and you can be charged with a felony. Or "by means of transportation"! And you are going across state lines. I know of confiscation on vehicles for transporting illegals just across town.
Encouraging and Harboring Illegal Aliens
Penalties upon conviction include criminal fines, imprisonment, and forfeiture of vehicles and real property used to commit the crime. Anyone employing or contracting with an illegal alien without verifying his or her work authorization status is guilty of a misdemeanor. Aliens and employers violating immigration laws are subject to arrest, detention, and seizure of their vehicles or property. In addition, individuals or entities who engage in racketeering enterprises that commit (or conspire to commit) immigration-related felonies are subject to private civil suits for treble damages and injunctive relief.
It is a violation of law for any person to conceal, harbor, or shield from detection in any place, including any building or means of transportation, any alien who is in the United States in violation of law. HARBORING MEANS ANY CONDUCT THAT TENDS TO SUBSTANTIALLY FACILITATE AN ALIEN TO REMAIN IN THE U.S. ILLEGALLY. The sheltering need not be clandestine, and harboring covers aliens arrested outdoors, as well as in a building. This provision includes harboring an alien who entered the U.S. legally but has since lost his legal status.