Exclusive look at results of expanded ATF, CPD Crime Gun Intelligence Center

CHICAGO (WLS) -- A major enforcement effort targeting illegal firearms and machine-gun conversion devices linked to traffickers and other violent activity in Chicago has netted more than 170 guns and resulted in over 40 arrests.

The investigation was conducted through the Crime Gun Intelligence Center, or CGIC. It's a collaborative effort between ATF, CPD and prosecutors at every level in the Chicago area.

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Its sole purpose it to apprehend the most violent and pervasive criminals involving guns on Chicago's streets. Agents and officers told the ABC7 I-Team the two-month gun crime crackdown is significant, yielding some unexpected results.

"We had our agents on the street every day with our partners and proactively buying these off the most violent offenders in Chicago," said Jonathan Maniff, Assistant Special Agent in Charge of the Chicago ATF field division.

Authorities outlined for the I-Team how over the past 60 days, 41 offenders were charged and 171 firearms, long guns, machine guns, and pistols, along with 64 gun switches also known as "auto sears" were recovered.

Those switches can turn a semi-automatic handgun into a fully automatic killing machine.

"We're seeing a lot more machine gun converging devices used in shootings across the city, and we wanted that to be our priority moving forward, " said Maniff, "Some of the offenders that we charged during this initiative shot an MCD in a park threatened a mass shooting, and also somebody else that was on parole for killing a 14-year-old."

He also explained that many of the guns recovered are connected to Chicago homicides and prior shootings in the city.

It's all part of the collaboration between ATF, the Chicago Police Department, and prosecutors at the federal and local level at CGIC.

"It's a small number of offenders that are causing so much violence in our city, and when we are able to conduct focused investigations and take out the right people and hold them accountable, and the State's Attorney's Office and the US Attorney's office works with us to detain them when appropriate, that at the end, that's going to make our streets much safer," said Chicago Police Deputy Chief of Detectives Kevin Bruno who also emphasized that a haul of that many illegal weapons in so short a time would not be possible without the essential CGIC partnership.

"It's very dangerous work. When you do an undercover buy it's a very risky operation but when you do that it allows you to build a strong case," he said.

A federal complaint outlines one such case against an Indiana man accused of illegally trafficking firearms from Indiana. A federal complaint lays out how agents conducted surveillance, controlled buys, even obtaining messaged photos of the weapons allegedly on offer.

But beyond heavy firepower law enforcement is up against on Chicago streets, Maniff said gun switches are especially concerning and being used at an exponential rate.

"The fire power it can be as bad as a long gun or a rifle or something like that," Maniff said. "With a machine gun conversion device attached to a semi-automatic pistol, it can shoot up to 50 rounds in less than two seconds."

Even though the 60 day enhanced enforcement period is over ATF said their efforts to stop gun switches from flooding the Chicago area continue with increased efforts to hold those charged with possessing switches. They say this is not over.