Despite long-standing rules prohibiting passengers from carrying guns on aircraft, the Transportation Security Administration continues to confiscate five guns a day at the nation's airports, a new survey from Northwestern University's Medill National Security Journalism Initiative found.

The number of guns taken away from passengers at security checkpoints jumped 20 percent in 2013 to 1,828. That is up from 1,120 three years ago. Of those taken, 84 percent were loaded and one in three had a bullet in the chamber ready to fire, the survey found.

Atlanta had the most offenders with 110 guns seized. Dallas at 98 and Houston at 67 were second and third followed by Phoenix, Denver, Nashville, Orlando, Seattle, Fort Lauderdale and Las Vegas. There were 17 confiscated at Minneapolis-St. Paul International Airport. One each was found at airports in Brainerd and Rochester, Minn.

During the period from January 3-9, 2014, screening agents found 28 firearms in luggage at checkpoints. Of those, 20 were loaded and five had rounds chambered, the TSA said.

In addition, 17 stun guns were discovered in carry-on bags at the nation's airports, including two in the Twin Cities.

Two types of guns, a .380 and 9mm, accounted for 46 percent of the handguns taken during 2013 at the nation's 207 airports.

It is illegal to carry a handgun aboard a commercial airliner; guns must be part of checked baggage and meet certain guidelines. The TSA notifies local authorities when a gun is found at security checkpoints; the local authorities determine whether to make an arrest, issue a ticket or taken other action.