NEW YORK (CBSNewYork/AP) — The Brooklyn district attorney offered more details on Tuesday of a probe into alleged firearms trafficking from Atlanta to New York.

A former Delta baggage handler, 31-year-old Eugene Harvey, is accused of helping smuggle guns aboard passenger jets bound for New York City.

Investigators said the guns — some loaded — were hidden in carry-on baggage.

“It is a very significant case in terms of concerns about national security the idea of getting guns in large numbers onto planes,” New York City Police Commissioner Bill Bratton said.

Brooklyn District Attorney Ken Thompson said the case is a wake up call for the nation, CBS2’s Steve Langford reported.

“This scheme really poses a threat in terms of terrorism,” said Thompson. “They could put guns on the plane this time, they could easily have put a bomb on those planes.”

The charges had some passengers jittery.

“I would expect them not to be putting illegal guns inside of bags, I mean, I don’t know, that’s kind of crazy,” one man said.

“I don’t like the sound of it,” another man said.

As CBS2’s Weijia Jiang reported, Harvey was not subject to security screening like passengers.

“It’s inconceivable after 9/11 this kind of thing can go on,” Richard Gonzalez said.

Harvey was arrested Saturday in Atlanta. A FBI affidavit said there was enough evidence to charge him with trafficking firearms, violating airport security and aiding others in the scheme.

An alleged accomplice, former Delta employee Mark Quentin Henry, was arrested in New York on Dec. 10 in a weapons trafficking investigation after an undercover agent bought a gun from one of his accomplices, according to the affidavit filed on Dec. 19. The investigation targeted firearms that were being sold in New York that had been purchased in the Atlanta area.

“There are multiple layers of security — normally if you fail on one level you catch them on the next. In this particular instance that didn’t happen,” said Douglas Laird, former Northwest Airlines security chief.

Police say Henry has been sneaking weapons into the city for more than two decades.

“We know that he gun smuggling went back to 1991. This person has literally facilitated genocide on the Brooklyn streets,” Thomas Purtell, Organized Crime Control Bureau, NYPd, said.

“This is one that we’re going to have to take a very close look at; how was this possible, how were they able to, over a period of time, move significant numbers of firearms from apparently Atlanta airport into New York City,” Bratton said.

Authorities looked at Henry’s cellphone, airport surveillance footage and security records and determined that he conspired with Harvey to get the guns past security. Cellphone records showed the two had communicated via text message 12 times shortly before Harvey’s flight departed Atlanta for New York City on Dec. 10.

When Henry was arrested, authorities confiscated a backpack that contained a smaller bag with 18 handguns inside. Henry told investigators he traveled from Atlanta to New York with the guns and ammunition in his carry-on bag, which would not have made it past TSA screening.

Investigators said Harvey was assigned to work in the baggage transfer room at Hartsfield-Jackson Atlanta International Airport, which is within a designated secure area. Investigators said security records show Harvey used his employee access card to enter the secure area just before 7 a.m. the day of Henry’s flight to New York.

Investigators said security footage showed Henry carrying a backpack and walking toward a gate in the B concourse around the same time he began texting Harvey. Harvey later entered a men’s restroom across from the gate where Henry was waiting, and security footage recorded Henry walk into the same restroom soon after. A minute later, Henry walked back out carrying the backpack where the guns were later found.

Henry later traveled to the A concourse and flight records show he departed from gate A1, investigators said in the affidavit.

Federal authorities accuse Henry and Harvey of conspiring to smuggle guns through the airport several times. Between May and Dec. 10, Henry supplied 129 handguns and assault rifles to a co-conspirator who then made sales to an undercover officer, according to the affidavit.

“Between may 2014 and December 2014, Mark Henry literally took about 20 flights with guns on him,” Thompson said.

Henry, a former baggage handler and ramp agent, was fired from the airline in 2010 for abusing its buddy pass system. He used pass benefits belonging to his mother, a retired Delta gate agent, to arrange for the flight between Atlanta and New York, according to the affidavit.

“Delta is cooperating with authorities in this investigation. We take seriously any activity that fails to uphold our strict commitment to the safety and security of our customers and employees,” airline spokesman Morgan Durrant said in an emailed statement.

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