SANTA ANA (CBS) — A Spanish teacher at Orange High School faces charges of having a sexual relationship with one of his students.

Scott Adrian Peterson, 48, of Anaheim, will make his first court appearance Thursday. Peterson is currently free on $100,000 bail.

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Peterson met the victim, a 17-year-old girl, when she was one of his students at the school, according to Deputy District Attorney Katherine David said, and would hang out with the teen outside of school, taking her to places like Disneyland.

Investigators are still determining when they began a sexual relationship, but in April, he took sexually explicit pictures of them together, David said. Peterson also allegedly sent sexually explicit text messages to the girl about their relationship.

The two would meet regularly to have sex at a motel and in a riverbed in Orange near Angel Stadium and the Century Stadium 25 movie theater, David said.

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One of the girl’s family members grew suspicious of the relationship and found the text messages on her phone, David said. The family member told the girl’s mother, who went to police.

Peterson moved out of his home about the same time he was placed on leave from the high school as his supervisors began an internal investigation, so police initially had trouble finding him, David said. He was arrested on Dec. 2.

“They pinged his new cell phone and the ping came around the area of the riverbed,” David said. “All of the detectives were driving around there and they just so happened to spot (the victim’s) car.”

About 15 minutes after the girl left, Peterson came out of the riverbed area and was arrested, the prosecutor said.

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