FLORENCE, Ariz. (AP) -- An 18-year-old Arizona high school senior appeared in court Friday after a second arrest amid accusations that he is a serial sex predator who assaulted nearly 20 students.
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.
Babeu also said Kost threatened and harassed the victims to such an extent that two fled the state and one attempted suicide.
"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.
The investigation was initiated after the Sheriff's Office received a call March 25 from someone reporting that Kost had sexually abused and molested five teenage girls.
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.
One victim told investigators that Kost sexually assaulted her several times throughout their 10-month relationship. According to the documents, the victim said she was at his house in November 2012 when his mother left for the grocery store. Kost allegedly used the opportunity to sexually assault her on a sofa, in his bedroom and in a dining room.
Another victim said she was 15 years old when Kost allegedly pinned her against a wall at a park after a homecoming dance last October.
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."
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."
Babeu also said he was troubled by the fact that Kost befriended the accusers and their families.
"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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