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NORTH COLLEGE HILL, Ohio -- Surveillance video from the cafeteria at North College Hill High School shows security guard Christopher Files enter a teachers lounge with his cell phone at the same time the school received its first bomb threat Monday, police say.
Police Chief Ryan Schrand said Files, 20, made threatening calls that led to school evacuations three days in a row.
There are no cameras inside the teachers lounge, Schrand said, but investigators believe the video shows Files immediately before and after the first threat.
Tuesday's call demanded money, Superintendent Gary Gellert said, but the others on Monday and Wednesday threatened to bomb the school with no additional demands.
"Something to the effect of 'give me money or I'm going to blow up the school,'" Gellert said. "The others just threatened to bomb the schools."
Police worked with Cincinnati Bell to try to identify the phone making the calls to the school. The calls were made from Files' cell phone from inside the school, Schrand said. Police called the phone number and located it in the school.
When police confronted Files about the phone, Files confessed to making the calls, Schrand said. He said he did not have a bomb in the school. He was arrested Wednesday and charged with three counts of inducing panic. His bond was set at $200,000 at an arraignment hearing Thursday.
Files, a contracted worker, was hired after social media threats caused safety concerns at the school, the superintendent said.
"(Files) was brought in because of safety concerns and he ended up causing more safety concerns," Gellert said.
Files passed a background check to take the job and has no criminal history, the police chief said said.