"We have been aggressively towing unattended vehicles on the curb," said Mike Blanton, RDU spokesman.
Travelers can unload and load their luggage at the curb at the airport but officials warn them to keep moving. Otherwise, their car could be viewed as a safety threat.
"A lot of people think we do that because it causes congestion, but it surprises me how many people forget a Ryder rental truck in Oklahoma City that was filled with fertilizer," Blanton said.
Security at RDU will be tight throughout the holiday season.
"If people set their bags down and walk away, chances are the incident will be reported immediately to our police department, and an officer will be dispatched to investigate the situation," Blanton said.
Brenda Mustian, a resident of Wilson, is very concerned about security because her son is coming from Berlin.
"Today is the 10-year anniversary of the flight that crashed in Scotland so it has really been on my mind a lot," Mustian said.
Other holiday travelers are not worried at all.
"My personal experience is yes, there are people out there who are a little crazy but I trust in the United States government so we should be OK," said Glenn Silverman, a traveler at RDU International.
Holiday travelers who are headed to big cities may see tighter security such as bomb-sniffing dogs and more FAA inspectors.