BALTIMORE (WJZ) — WJZ continues to investigate illegal guns on Baltimore’s streets. City police tell us the number of guns they’re linking to multiple crimes has doubled.

Mary Bubala explains why that is.

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It’s an epidemic–thousands and thousands of illegal guns in the hands of criminals walking the streets of Baltimore. So many are linked to multiple crimes.

It takes intense police work on the streets and inside the city crime lab to get those weapons locked away.

WJZ got rare access to the elite team of examiners working those guns.

“They’re a drop in the bucket,” said Dan Lamont, firearms examiner.

Bubala: “We know we live in a violent city, but when you see these guns in front of you… that’s just pure evidence.”

Lamont: “It’s one less out there killing somebody.”

Dan Lamont is in charge of the extensive gun library. It is where detectives turn when they need to test-fire a similar gun used in the crime they’re investigating–hopefully, leading to key clues in the case.

“If we have that same type of gun in here, we can take it off the wall, replace parts to it and be able to shoot that gun to be able to use for evidence, for bullets and cartridge cases on the microscope,” said Lamont.

The next step is firing a gun into a high-tech water tank and then fishing out the bullets–now imprinted with markings unique to the gun they were fired from.

The goal is to match the markings up with the illegal gun at the center of the investigation.

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“I’m going to take these bullets out, mark them and I’m going to actually compare them against any other fired evidence that’s in question,” said firearms examiner Chris Faber.

That’s where a CSI-type lab comes in.

Investigators showed us the intricate process of examining the shell casings, trying to link them to multiple crimes.

“If there’s a cartridge case that has markings that we can identify, I’m hoping to see if they’re going to match up to something,” explained Karin Lipski, firearms examiner.

When there’s a match, it’s a lead in the case.

Many times, it ends in an arrest and that illegal gun getting off Baltimore’s streets.

That is always the goal for crime lab director Steve O’Dell.

Bubala: “It’s significant just to even get one illegal gun off the street… that makes a dent in crime in the city of Baltimore…”

O’Dell: “Every gun counts. The fact of the matter is, the gun is the tool, so getting the guns off the street is going to change the crime picture. The shootings have to go down when the tools are not available.”

Once an illegal gun’s information is entered into the lab’s database, state and federal authorities can also access it to solve crimes they’re working on.

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City police tell WJZ working any kind of case can lead to the recovery of an illegal gun. Burglaries are especially important because many guns are stolen from people who bought them legally.