An investigation into a prison guard in North Carolina led deputies to large amounts of drugs and 99 guns inside a home, according to authorities.

On May 5, investigators from the Robeson County Sheriff’s Office executed a search warrant on a residence in Lumberton connected to 32-year-old Derek C. Madden, a prison guard at the Tabor Correctional Institution, according to a news release.

He has since resigned, according to WECT.

Inside the home, investigators found cocaine, fentanyl, prescription pills and other drugs, according to the release.

Authorities also found 99 firearms, the sheriff’s office said.

The discovery came after a months-long undercover investigation into Madden, WRAL reported. The investigation began when the office started examining drug overdose deaths in the area, according to the outlet.

Eventually, the investigation led authorities to Madden, Sheriff Burnis Wilkins told WRAL.

“It’s an unbelievable catch,” Wilkins told WRAL. “In my career, I’ve never seen this many guns taken from one location.”

Photos provided by the sheriff’s office show rifles with scopes, handguns and shotguns recovered from the scene.

In addition to the guns, Wilkins told WRAL that Madden was in possession of enough fentanyl to kill 12,000 people.

After authorities found the items the prison guard was arrested on May 5, the sheriff’s office said.

He was booked into Robeson County Detention Center on a $1,075,000 secured bond, WECT reported.

Madden was first hired as a correctional officer in 2016, WECT reported.

Madden faces multiple drug and gun-related charges, including nine counts of possession of a stolen firearm, two counts of trafficking opium or heroin, possession with intent to sell or deliver cocaine, two counts of possession with intent to manufacture, sell and deliver a scheduled II controlled substance and possession with intent to manufacture, sell and deliver a scheduled III controlled substance, according to the release.

Investigators believe that Madden was using a false Lumberton police badge and his power as a prison guard to allow for drugs and weapons to be sent to inmates, WRAL reported.

The Federal Bureau of Alcohol, Tobacco, Firearms and Explosives is aiding in the ongoing investigation, according to the sheriff’s office.

Lumberton is about 99 miles southwest of Raleigh.

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