An Ohio grand jury has decided not to return an indictment in the 2014 police shooting death of 12-year-old Tamir Rice, prosecutor Tim McGinty said Monday.

Now that the criminal investigation is completed, police officials in Cleveland will conduct an administrative review of the Tamir Rice shooting, Cleveland Mayor Frank Jackson said Monday, reports CNN.

The shooting has caused Cleveland to do "a lot of soul searching," Jackson said.

"In the midst of that soul searching," Jackson said, "we have made some changes. ... All of this is designed to better ensure that an incident like this will never happen again."

After the administrative review is completed, it's possible the police officers involved could face disciplinary action if the committee set to review the case determines polices or procedures were violated, Cleveland Police Chief Calvin Williams said.

"Both of the officers are and will remain on restricted duty. They have been on restricted duty since this incident happened," he said. "That's part of our process, not to allow officers involved in critical incidents to go back out there into the fray. They will remain on restricted duty until we complete the administrative process."