The investigation of McKee began in March after Serbian police uncovered several websites, apparently based in the U.S., that were distributing child porn.
McKee's attorney, Monica Foster, didn't respond to a phone message seeking comment Thursday.
Two other men, 44-year-old Gregory Evans, of Evansville, and 46-year-old Randall Allen, of Indianapolis, were arrested Nov. 15 and Dec. 14, respectively, on federal charges of possessing child porn.
Another Indianapolis man, 54-year-old Stephen Hill, faces a state charge of child exploitation, authorities said.
Evans' attorney, Michael Keating, declined to comment about the case. Attorneys for Allen and Hill could not be located.
The international investigation, dubbed "Operation Sunflower," was part of ICE's effort to find and rescue victims and arrest those who make and transmit child pornography. ICE Director John Morton said 123 child victims were identified during a five-week investigation that ended in early December
As part of the Indiana investigation, three girls under age 12 were identified as victims, the agency said. It provided no information on the girls.