Federal prosecutors accused a Delta Air Lines Inc. baggage handler and a former employee of the carrier of ferrying guns aboard a passenger flight as part of a larger gun-trafficking operation between Atlanta and New York.

The accused employee, Eugene Harvey of Atlanta, was arrested without incident on Saturday and made an initial appearance in front of a U.S. Magistrate Judge in Atlanta on Monday, said Federal Bureau of Investigation Special Agent Stephen Emmett. Mr. Harvey’s alleged accomplice, Mark Quentin Henry, was arrested...