PHILADELPHIA (CBS) — Prosecutors say one of the two suspects in custody in connection to the mass shooting on South Street over the weekend used a ghost gun. These homemade weapons are a major contributor to Philadelphia’s gun violence crisis.

Traditionally, manufactured guns have serial numbers and require a background check to purchase. On Monday, authorities said one of the guns used in Saturday night’s mass shooting required neither.

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It’s a discovery that some say is not surprising.

“I don’t think so, I mean, it was bound to happen,” said Adam Garber, executive director of CeaseFirePA.

The Philadelphia District Attorney’s Office confirmed Monday that 18-year-old Quran Garner used a ghost gun to fire into a crowd on South Street after a fight.

“It is at that point that Philadelphia police began to shoot after Quran Garner pulls a gun, has the gun out and looks in their direction,” Joanne Pescatore, chief of the homicide unit at the Philadelphia DA’s Office, said. “They shoot at him, shooting his hand.”

The chaos caused Garner to drop the ghost gun they say was equipped with an extended magazine.

“It’s like Ikea for guns,” said Garber. “There’s a kit you get. It says to put a hole here, attach it here and you have a firearm.”

Garber says a ghost gun is a firearm made of parts you can buy online and put together yourself that’s been increasing in popularity.

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“It’s not serialized. It’s not traceable and you don’t need a background check,” Garber said, “so if you can’t legally own a gun, it’s the gun of choice for you.”

According to the governor’s office, Philadelphia has been tracking the seizure and recovery of ghost guns from crime scenes since 2019.

The city recorded 95 seizures in 2019, 250 in 2020 and 571 in 2021.

The guns are legal in Pennsylvania but not Philadelphia after the city passed a bill prohibiting the use of a 3D printer to make a firearm.

“When you are allowed to purchase weapons whose sole purpose is to kill human beings, there’s got to be some common sense that says that the government, we can’t allow that to happen,” Mayor Jim Kenney said.

Under Pennsylvania state law, ghost guns are not considered firearms, so background checks and serial numbers aren’t required to buy and sell them.

Pennsylvania Attorney General Josh Shapiro says he’s been working to change that saying, “We have demanded the legislature close the ghost gun loophole for years. Until action is taken, we are going to lose more lives to these untraceable weapons.”

Shapiro is Pennsylvania’s Democratic nominee for governor.

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The mayor says they’ve taken about 6,000 guns off the street just last year.

Jasmine Payoute