Police in Illinois are searching for four suspects who rammed a stolen vehicle into a gun range to gain entry, then proceeded to steal more than 20 firearms.

It happened around 3 a.m. Monday, according to FOX 32 Chicago. Oak Forest police responded to an alarm call at the Eagle Gun Range.

Surveillance video shows the thieves wearing stocking caps and masks inside the facility as they steal approximately 23 guns, officials said.

"Concerning, yes," customer Giovanni Magana told WLS. "They're gonna have a bunch of guys running around shooting, selling guns under the table, so it's scary, you know?"

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Two IL gun range suspects

Two suspects who broke into an Illinois gun range and stole nearly two dozen guns. (City of Oak Forest)

The range has been a target by criminals in the past, the TV station reports. Five years ago, thieves used a brick to smash a window prior to getting away with 40 guns. 

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Close up IL gun range suspect

A close up look at one of four suspects who broke into an Illinois gun range and got away with nearly two dozen firearms. (City of Oak Forest)

IL gun range thieves composite

Police in Illinois are investigating after four suspects rammed a stolen vehicle into a suburban gun range to gain entry, and then proceeded to steal more than 20 firearms from the business Monday morning. (City of Oak Forest)

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The investigation is ongoing, and agents from the Alcohol, Tobacco and Firearms Agency are assisting the Oak Forest Police Department. Anyone with information is urged to contact investigators at 708-687-1376.