CINCINNATI (WKRC) - A Greater Cincinnati teacher has been arrested and faces federal child porn charges.

Mark Altherr wrote about sexually abusing children on a website that describes itself as a "child pornography community", according to court papers. It apparently exists to "serve the pedophile community around the globe."

According to court papers, Altherr had been a user on that unnamed website since 2021 and had at least 262 posts. He had been designated a senior member.

The FBI went to conduct surveillance on Altherr on July 26 but they weren't able to find him or his vehicle at his Woodvalley Lane home. Investigators pinged his phone which indicated he was in Columbus. The FBI found Altherr and his SUV later that evening at a hotel in Columbus. The FBI went to his hotel room, announced themselves and said Altherr opened the door but quickly shut it, to try to keep them out.

They took Altherr into custody. Agents seized a laptop, cellphone, two suitcases, and a bookbag.

The FBI then searched Altherr's home where they said they found two USB drives with child porn on them. Court documents indicated he lived alone.

According to the FBI, Altherr is a fitness education teacher in the Oak Hills Local School District.

"Investigators are now working to identify all of the victims in this case," said Kenneth L. Parker, United States Attorney for the Southern District of Ohio. "Our office and the FBI encourage anyone who might have information about victims to report it to the FBI's victim resource page."

"The FBI is always working to protect children in our community," said FBI Cincinnati Special Agent in Charge Elena Iatarola. "As we continue to investigate this matter, we appreciate the support of the public in coming forward with any information they may have about potentially inappropriate actions of Mr. Altherr."

If you have information about this case or believe you are a victim, click here.

Altherr is set for a detention hearing on August 1. Distribution of child pornography is punishable by at least five years and up to 20 years in prison. Possession of child pornography is punishable by up to 20 years in prison.

Oak Hills Local School District released a statement on the Altherr's arrest:

"Oak Hills Local Schools has been notified that Mark Altherr, a teacher at Delshire Elementary School, was arrested in Franklin County, Ohio by the FBI and charged with two class B felonies - possession and distribution of child pornography. Following district policy, Mr. Altherr has been placed on administrative leave and is prohibited from being on school grounds or having any contact with students or staff. Based on the evidence presented, the board of education intends to initiate termination proceedings. The Oak Hills Local School District is working closely with and fully cooperating with the FBI and law enforcement agents regarding the ongoing investigation. When more information becomes available, and legally permissible, we will share it with families and the community."