Three Forsyth County men will spend time in prison after they were convicted of various child sexual exploitation charges, officials said.

Steven Vinnenberg, 66, Robert Harley Martin, 38, and John O’Dell, 40, all of Cumming, each pleaded guilty to charges involving sex crimes against children, according to Forsyth sheriff’s office spokeswoman Stacie Miller.

The men were among 24 people who were arrested last September in connection with a child sex sting, Miller said. The four-day undercover operation, called “Operation Just Cause,” was a cooperative effort between fourteen law enforcement agencies north of Atlanta, Miller said.

Those taken into custody faced charges including aggravated child molestation, child sex trafficking, sexual exploitation of children and distribution of child pornography.

Vinnenberg was charged with obscene internet contact with a child, and Martin was charged with criminal attempt to commit child molestation. They will serve four and eight years in prison, respectively. Vinnenberg will also serve 26 years on probation, while Martin will serve seven years.

O’Dell, whose charges are not clear, will serve one year in custody and 19 years on probation.

Roger Nicholson, 44, of Gainesville, was also arrested during the operation on charges that did not involve child sex abuse, Miller said. Officials said Nicholson was a passenger in a vehicle that was pulled over during the sting. Investigators found meth in the vehicle, Miller said.

Nicholson was sentenced to five years probation after pleading guilty to violation of the Georgia Controlled Substances Act and possession of methamphetamine.

In other news: 

The investigation is on Crump Road in Cartersville, off Cassville Road.