(NEW YORK) — Just weeks before he was killed along with three others in a hail of gunfire at a Sweet 16 birthday party in Dadeville, Alabama, 19-year-old Marsiah Collins told his father about a growing national crime trend that had reached their community: teenagers armed with weapons converted into machine guns with a cheap accessory available on the internet.

One of the seven handguns involved in the April 15, 2023, rural Alabama mass shooting that also left 32 partygoers injured at a dance studio was fitted with a tiny illegal device often dubbed a “Glock switch” that turns semiautomatic Glock weapons into fully automatic firearms, according to the Alabama Law Enforcement Agency. Investigators collected 89 shell casings at the Dadeville crime scene.

“It was Marsiah who told me that these kids out here have handguns that are like machine guns. I never will forget that conversation. He told me out of his own mouth, kids as young as 14 or 15,” Collins’ father, Martin Collins Jr., told ABC News. “It’s the worst invention in American history, in world history.”

With the official start of summer less than a week away, police across the nation are bracing for what one law enforcement expert described to ABC News as the “next level” of gun violence. Law enforcement officials attribute a dramatic increase in the number of shots fired at crime scenes across the country to a lethal combination: multiple people drawing guns in crowded settings to settle disputes and a growing number of criminals using Glock firearms converted to machine guns and equipped with extended magazines.

“What that’s telling us is that criminals who already are owning these handguns illegally are now taking it to the next level, and they are trying to maximize the destruction that they cause,” Jillian Snider, a former New York City police officer and an adjunct lecturer at John Jay College of Criminal Justice, told ABC News.

Four shootings, one weekend, 263 gunshots, 42 injured, two fatally

In the first weekend of June, police in four U.S. cities investigated shootings in which a minimum of 25 shots were fired to a barrage of more than 100 bullets. In those four shootings alone, 42 people were shot, two fatally, authorities said.

The shootings during the weekend of June 1-2 included one at a birthday party in Akron, Ohio, that left one man dead, 28 people wounded, and police collecting 45 shell casings from five different weapons in over a blocklong crime scene, authorities said. That weekend also included three men being shot, one fatally, in a Joliet, Illinois, drive-by shooting on a home, where police discovered 25 shell casings. And in St. Louis, Missouri, six people were shot outside the Playground Bar & Grill, where police collected more than 100 shell casings.

Detroit Police Chief James White told ABC News that when he heard detectives had recovered 93 shell casings from a June 1 shooting that left four people wounded, two critically, at a late-night party in north Detroit, his gut feeling told him a modified gun was used.

“When you get that number of shell casings in an incident like that, it passes through your mind that obviously it was either semiautomatic or an automatic weapon involved. I was not surprised that it was a Glock switch. Unfortunately, they’re becoming all too common in our community,” White said.

White said eight guns were recovered at the crime scene, including an AK-47 rifle. Two of the weapons were found to be stolen, including the one equipped with a Glock switch, he said. No arrests have been made, but White said police are making progress in the investigation and expects those responsible to be in custody soon, adding, “There were shots back and forth between some folks who had problems with some folks at the party.”

“We’re seeing a lot of Glock switches, we’re seeing a resurgence of the AR handgun and rifle,” White said. “They’re falling into the wrong hands. They are falling into the hands of teenagers and young adults. Folks are making just horrible decisions, impulsive decisions with the inability to resolve relatively basic conflict.”

White said there is no other reason to have guns with fully automatic conversion devices, other than to “cause mass destruction quickly amongst large groups of people.”

“If no one cares about that, I think we’ve got a bigger problem than the Glock switch itself. Everyone should care about this, every single human being should care about this,” said White.

During a news conference last week, St. Louis Police Chief Robert Tracy noted that of the six people shot in the gunfight outside the Playground Bar & Grill, two were convicted felons and two were undocumented gang members.

“Knowing people with the highest propensity for violence, carrying guns, known to each other is sometimes a recipe for disaster,” Tracy said. “Too many guns are in the hands of people that are going to use them in incidents like this.”

570% increase in Glock switch seizures

According to a 2023 report by the federal Bureau of Alcohol, Tobacco, Firearms and Explosives, 5,454 guns with machine-gun conversion devices were taken into ATF custody at crime scenes between 2017 and 2021, a 570% increase in the five-year period. Between 2012 and 2016, the ATF seized 814 guns equipped with such devices, according to the report.

“From a public safety perspective, from a public health perspective, this is a problem that, unfortunately, is disproportionately concentrated in the country’s most economically vulnerable communities of color,” Jens Ludwig, co-director of the University of Chicago Crime Lab, told ABC News.

Law enforcement officials said the machine-gun conversion devices — also called “auto sear” — are believed to be mostly manufactured overseas and sold on the internet. They can even be made with 3D printers and cost as little as $20 to buy, officials said.

“Let me be clear: Making, selling and just having these kinds of machine gun conversion devices is against the law,” ATF Director Steven Dettelbach said during a February 2023 gun violence prevention forum held in New York City. “This is a problem that needs to be focused on immediately. These devices are flooding our communities.”

An alarming number of high-profile shootings involving multiple shooters or converted fully-automatic weapons have erupted in the first five months of 2024 in American cities both big and small.

On March 6, eight teenagers, ages 15 to 17, were shot at a Philadelphia SEPTA bus stop by three masked gunmen who opened fire, spaying more than 30 shots in a matter of seconds, according to the Philadelphia Police Department. One of the guns seized in the crime was a Glock 22 pistol with a Glock switch and laser sights. Five suspects, ranging in age from 15 to 19, were arrested and charged in the shooting, according to police.

On April 1, four people were injured in a shooting at a block party at a public housing development in Paris, Texas, when a dispute between two men escalated into a gunfight that involved multiple firearms. Paris police reported that at least 80 shell casings were collected at the scene, but have not said if any of the weapons were modified machine guns. A 42-year-old man was arrested in the shooting and charged with unlawful possession of a firearm by a felon in a weapon-free zone, according to police.

On April 11, 2024, a 14-year-old boy was arrested in Columbia, South Carolina, and charged with murder in the fatal shooting of a 16-year-old boy and his father during a robbery, according to the Columbia Police Department. Police said the young suspect, who shot himself in the leg during the incident, was armed with a pistol illegally modified with a switch.

On April 20, two people were killed and seven were injured at a block party in Memphis, Tennessee, when multiple people pulled out guns, including at least one fitted with a switch, and opened fire, according to the Memphis Police Department.

“I think that the thing that is deeply unhelpful from a public safety perspective is the simultaneous development of these Glock switches that turn semiautomatics into basically machine guns together with the lapse of the high-capacity magazine ban,” said Ludwig, referring to the law banning magazines holding more than 10 bullets which was signed into law President Bill Clinton in 1994 and expired in September.

“So now you’ve got a 16-year-old kid with basically a machine gun that can fire 100 rounds with the trigger depressed like that, just driving around the South Side of Chicago. You can see how that’s a terrible recipe for disaster,” Ludwig said.

What is a ‘Glock switch’?

Glock switches, also referred to by law enforcement as “auto sears,” are devices about the size of a quarter that can be easily fitted onto the back of a handgun’s slide mechanism. Once attached, the metal or plastic part manipulates the gun’s trigger bar, turning the weapon from a semiautomatic, which requires a pull of the trigger for each shot fired, into a fully automatic weapon in which numerous shots can be fired by depressing the trigger and holding it, experts said.

A first-of-its-kind lawsuit filed in March by the city of Chicago against Glock Inc. is attempting to force the gun manufacturer to retool its weapons to make it more difficult to convert them into machine guns with a switch. The suit alleges Glock is aiding and abetting in the proliferation of illegal machine guns.

Georgia-based Glock Inc. does not make the switches and has no affiliation with those who manufacture them. The company did not respond to requests from ABC News for comment.

According to the lawsuit, the Chicago Police Department said that between the beginning of 2021 and Dec. 31, 2023, officers recovered more than 1,000 Glock guns that had been modified into automatic weapons.

“These terrifying weapons have caused death and destruction throughout Chicago: they have been recovered in connection with homicides, aggravated assaults, batteries, kidnappings, burglaries, home invasions, carjackings, and attempted robberies,” according to the lawsuit.

The lawsuit alleges that Glock Inc. has known about the dangerous work-around for years, but has made the “wilful decision to not take any meaningful action to address this problem.”

“Indeed, in stark contrast to Glock pistols, the process of modifying most other popular pistols into machine guns, such as those produced by Smith & Wesson or Sig Sauer, require time-consuming and difficult engineering well beyond the capability of most civilians,” the lawsuit alleges.

Shooting fatality rate rises in Chicago

Ludwig said the surge in the number of modified guns on Chicago streets coincides with an increase in the fatality rate per shooting in the city. He said a study done by the University of Chicago Crime Lab found that fatalities in shooting incidents in Chicago have risen from 13% in 2010 to 19% in 2023.

“Unfortunately, we have thousands and thousands of people shot in Chicago every year. So an increase of something like a third or more in the shooting fatality rate winds up generating a huge increase in the number of murders even if you hold the number of shootings constant,” Ludwig said. “Just that increase in the shooting fatality rate means that we have 1/3 more murders in Chicago today than we would if shootings were as lethal as they were back in 2010. So it’s a really, really big deal.”

Snider, who is also director of criminal justice and civil liberties at the R Street Institute, a public policy think tank in Washington D.C., said the ages of people caught with modified guns “is petrifying.”

“What happens is because they’re untrained and unskilled, and these are dangerous weapons, oftentimes, an innocent person who has nothing to do with the situation gets caught in the crossfire,” Snider told ABC News, adding that the rapid recoil on such modified weapons makes them almost uncontrollable for adults and teenagers with no training.

Snider said the converted weapons are also being used on law enforcement officers more frequently.

On April 12, 2024, in Memphis, Tennessee, police officer Joseph McKinney was killed and two other officers were wounded in a firefight that erupted as they responded to a suspicious vehicle call. They were confronted by two teenagers in the car, one firing a handgun modified with a Glock switch, according to the Memphis Police Department. An 18-year-old suspect was killed and a 17-year-old accomplice was wounded, police said.

In September 2021, Houston Police Officer William “Bill” Jeffery was killed and another officer was seriously wounded while serving a narcotics arrest warrant on a suspect who opened fire on them with a weapon that had been turned into a machine gun, according to the Houston Police Department. The officers exchanged gunshots with the suspect, killing him, officials said.

In November 2023, a 20-year-old murder suspect with a modified handgun allegedly opened fire on Dallas police officers and U.S. Marshals attempting to arrest him, according to the Dallas Police Department. One officer was shot in the leg during the gunfight, police said.

“Most officers’ guns carry either 11 or 16 rounds. That’s most officers. And we’re seeing more and more that … people are able to get off 50 to 100 shots in under a minute [with these modified weapons],” said Snider, who retired from the NYPD in 2020.

‘Operation Texas Kill Switch’

Many states and cities seeing large increases in the number of gun conversion devices seized by police, are taking action.

On Monday, federal prosecutors in Texas announced the launch of “Operation Texas Kill Switch,” a statewide initiative targeting illegal machine gun conversion devices. Officials said that between 2017 and 2023, Texas-based ATF agents seized 991 Glock switches; 490 in just the last year, officials said.

“Today is an important step to put on notice those who traffic in switches and who use switches. We will hold you to account,” said Alamdar Hamdani, U.S. attorney for the Southern District of Texas.

Hamandi said his office was teaming up with the ATF and Crime Stoppers to offer cash rewards for information leading to the arrests and prosecution of suspects who possess gun conversion devices or 3D printers used to manufacture them. Hamandi said anyone caught with such devices could face a maximum sentence of 10 years in prison.

New York lawmakers proposed legislation in May that would prohibit the sale of semiautomatic pistols that can easily be turned into automatic weapons and require firearm manufacturers to take steps to ensure their handguns cannot be easily turned into machine guns with switches.

The Alabama House of Representatives passed a bill in May to ban the possession of any part or combination of parts designed to convert a firearm into a machine gun. The bill, now being considered by the state Senate, would also make possession of such devices a Class C felony, punishable by up to 10 years in state prison.

‘Weapons of war’

Martin Collins Jr. said that while he is encouraged to see states and cities taking action to stop the spread of converted guns like the one used to kill his son, an honor student and athlete who was planning to attend Louisiana State University, he remains skeptical that real change will occur.

“We have had numerous attempts to ban switches in this country, but it always ends up in political discourse,” said Collins, a lawyer. 

“While they’re inactive, we continue to bury America’s children of all races and colors,” Collins said.

A Marine who served in Iraq, Collins said he never thought his son would be killed in a small American town like Dadeville, Alabama, by someone using a “weapon of war.”

“It’s profoundly out of control. In the Marine Corps for an M16A4 service rifle, you have a 30-round magazine. You don’t even load 30 rounds because the magazine jams. So you put 27 in and the last three you pray, but that’s also to control the rate of fire,” Collins said. “If the military is concerned about the number of rounds being expended, then we as a country should also be concerned about that.”

In the year since his son was killed, Collins said he has spoken with local, state and federal officials, telling them converted guns are not just killing victims, but devastating entire families.

“I tell every congressman, congresswoman, senator, state representative, local representative until you walk into a funeral home and see your 19-year-old son wrapped in plastic from the morgue and knowing what they did to him, you will never understand,” Collins said. “But I live with that every day because I went to see what they did to my son.”

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