The investigation included crimes committed in connection with the case against two members of the celebrated Steubenville High School football team as well as a separate alleged rape that happened in April 2012, four months before the assault that drew nationwide attention over allegations that prosecutors should have charged more players.
Hacker activists helped propel coverage of the rape case and press allegations of a cover-up, including reposting of a 12-minute Internet video made within hours of the attacks in which a former Steubenville student joked about the victim.
Ohio Attorney General Mike DeWine convened the grand jury to look into the behavior of school administrators and other adults in the community after the two players were convicted last March. Under the law, educators are required to report allegations of child abuse.
Two people had already been charged before Steubenville Superintendent Mike McVey, strength coach Seth Fluharty, volunteer football coach Matthew Belardine and elementary school principal Lynnett Gorman were charged Monday.
McVey's charges include felony counts of obstructing justice and tampering with evidence and a misdemeanor charge alleging he made a false statement in April 2012. McVey wasn't immediately available for comment, and messages were left for his attorney.
Belardine, whose house authorities said was the scene of the underage drinking party that preceded the rape last summer, faces several misdemeanor charges, including making a false statement and contributing to underage alcohol consumption. Belardine will plead not guilty, said Columbus attorney Brian Duncan.
Fluharty was charged with failing to report possible child abuse in August 2012. Columbus attorney Tom Tyack said he had been contacted to represent Fluharty but could not comment.
Gorman is charged with failing to report possible child abuse in April 2012. Her attorney, Stephen LaMatrice, said she will plead not guilty and the charge isn't connected to the football players' case, but declined to elaborate.
DeWine announced the grand jury's creation March 17, the day a judge convicted Ma'Lik Richmond and Trent Mays of digitally penetrating a West Virginia girl after an alcohol-fueled party that followed a team scrimmage.
The grand jury earlier charged the Steubenville schools' information technology director with tampering with evidence, obstructing justice, obstructing official business and perjury. The panel also indicted that man's daughter on theft and receiving stolen property charges unrelated to the rape case. Both pleaded not guilty.
The case has long been marked by allegations that more football players should have been charged and that police and prosecutors tried to cover up aspects of the case early on. Authorities counter that the two teens were arrested and charged within days of the attack.
DeWine said he believes the grand jury's work is done, barring any new evidence, and acknowledged people may wonder why still others weren't charged.
"It is simply not sufficient that a person's behavior was reprehensible, disgusting, mean-spirited or just plain stupid," DeWine said.
A group of about a dozen Steubenville High School students spent their lunch break at the curb outside the scene of DeWine's news conference, chanting the school's "Big Red" cheers at passing cars: "We love Big Red, yes we do. We love Big Red, how 'bout you?'"
The students said they were expressing their support for their school, not any party involved in the investigation.
Big Red football is a big deal in the economically depressed city of about 18,000, a former steel town that shed thousands of jobs in past decades.
Michael Moore, 21, who had attended the school, said it was disturbing to hear the investigation reached the upper levels of the community's educational leadership.
"These are people we are supposed to look up to," said Moore, 21. "They can't be doing stuff like that."
Derek Smith, 47, whose son is a fifth grade student at the school overlooking the stadium home of the football team, said he was upset that school leaders might have been involved.
"Of course, it's always disturbing when you find out that the people that are in charge of your kids at school have been charged with this kind of thing," he said.
Richmond, 17, was convicted of rape and sentenced to a year in the juvenile prison system. Mays, also 17, was convicted of rape and of using his phone to take a picture of the girl naked and sentenced to two years in juvenile detention.
Associated Press writers Kantele Franko, Mitch Stacy and Andrew Welsh-Huggins in Columbus, Ohio, contributed to this report.