FLORENCE, Ariz. (AP) -- An 18-year-old Arizona man accused of being a serial sex predator who targeted fellow high school students made his first court appearance Friday since being arrested on new charges.
A Pinal County judge ordered Tyler Kost held without bond based on allegations that include additional cases reported after his previous arrest.
County Attorney Lando Voyles said his office has not yet filed any charges and is allowing the Pinal County Sheriff's Office to continue investigating.
Sheriff Paul Babeu said Kost was arrested Thursday on 25 additional charges. Babeu said there are 18 reported victims, but he expects those numbers to rise.
"This is a serious and serial sex offender and rapist," Babeu said during a news conference. "We're approaching 20 victims. There likely will be others that come forward."
A message left seeking comment from Kost's attorney, Christine Whalin, was not immediately returned Friday.
Kost, who is a student at Poston Butte High School in Florence, is accused of multiple counts of sexual conduct with a minor, sexual abuse and sexual assault. According to the arresting documents, many of the alleged incidents occurred at Kost's home or inside a vehicle. Babeu said the incidents appear to go back three years.
Kost lives in the San Tan Valley, a bedroom community of about 87,000 named for its location in the foothills of the San Tan Mountains. The area, which lies 45 miles southeast of Phoenix, is known for golf courses and hiking trails.
Principal Tim Richard said Kost had been suspended from campus since early April and was completing his school work from home.
"As soon as we learned that these allegations were made and that detectives informed us he was under investigation, we immediately took steps to make sure he wasn't on our campus," said Richard, who oversees a school of 1,700 students. "As long as I'm the principal, he will not be on this campus."
According to the Richard, Kost reported being the victim of bullying around the time the investigation started.
"He did report that he was being bullied, but he never presented us with any evidence of that," Richard said.
Meanwhile, a crisis team of counselors and school psychologists was at the campus Friday.
"The climate and culture on this campus is a very positive one," Richard said. "This is a real shock to a lot of people that something like this would happen."
According to Babeu, Kost threatened and harassed victims to such an extent that two fled the state and one attempted suicide.
"There was a clear breach of trust," Babeu said of Kost. "From all of the accounts of the victims, (Kost) is someone who is highly manipulative, very charismatic and charming in how he presented himself. And then things obviously turned."
The sheriff was also critical of the judge who released Kost on bond after the first allegations.
Kost was released on $10,000 bond after being arrested Monday on suspicion of two counts each of sexual assault and sexual misconduct with a minor.
The County Attorney's Office said it had requested a $100,000 bond, but Pinal County Judge Larry Wharton set it at $10,000.
A message left at Wharton's office seeking comment was not immediately returned Friday.
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