Christopher Kice, 41, of the 1100 block of Callaway Drive West, was arrested Monday night without incident, the FBI said.
According to the complaint, investigators were first alerted to Kice's possible involvement in the collection of child pornography by his employer, an unnamed Chicago-area law firm where Kice worked in the IT department.
An FBI news release says Kice's co-workers noticed that numerous large files with suspicious sounding names, such as "kiddie" and "pre-teen", had been downloaded on a company computer then transferred to removable storage devices.
According to the release, Kice's home was searched March 17. But it wasn't until this week that investigators realized that some of the images appeared to have been taken in Kice's home.