ROCHESTER — The investigation into a Rochester police officer who was suspended after allegedly posting offensive images is being turned over to an independent, outside firm, the city’s police chief said Friday.

Chief Roger Peterson also said the department’s professional standards manager, Scott Hildebrand, will be placed on paid leave until the investigation is over to avoid a potential conflict of interest.

“During the course of this investigation we were provided with additional information that, in my opinion, compromises our ability to provide a full, fair and impartial inquiry into this matter,” Peterson said in a statement.

Officer Ben Schlag was placed on paid administrative leave earlier this month as the department investigated allegations that shortly after a Black Lives Matter demonstration in the Twin Cities, he posted on Facebook an image of a car running over protesters. He also allegedly posted an item about shooting Muslims.

Peterson and Rochester Mayor Ardell Brede called for an immediate investigation.

The outside investigator will be chosen by the city of Rochester’s Human Resources Department.

As professional standards manager, Hildebrand was responsible for investigating complaints against officers. He is a civilian.

Peterson said Friday that placing Hildebrand on leave doesn’t mean there is a conflict of interest, but is a precaution to ensure the integrity of the investigation.

Peterson apologized for delaying the investigation, but says the investigation’s integrity outweighs the need for a quick resolution.

“I think everyone knows it’s an issue with some significant gravity,” he said.