A Palo Alto High School science teacher who allegedly touched a student in a classroom at the end of the school year was arrested by police on Wednesday night, June 15, for committing sex crimes against a minor.

Palo Alto police received a call on Monday, June 13, at about 8:44 p.m. from a parent who said their 15-year-old daughter had been assaulted by a teacher. The victim had recently completed ninth grade at Paly, and the suspect had been her biology teacher during her freshman year, which ended on June 2, according to police.

An investigation revealed that teacher Ronnie Farrell, 46, of Palo Alto, had been communicating with the victim using social media. He asked the victim to meet him at Paly on Tuesday, June 7, at 9 a.m. The victim regularly helped her teachers with chores in the classroom, and she agreed to meet him, police said.

Farrell allegedly led the victim to his classroom, where the two of them were alone. After conversing with the girl, Farrell allegedly put his hands under the victim's clothes and touched her breasts. He also allegedly took one of her hands and placed it on his groin over his clothing. He eventually told the victim to leave the classroom, police said.

Detectives who began investigating the case immediately after the parent's complaint found that Farrell continued corresponding with the victim via social media. He arranged to meet her at Paly on the evening of June 15. Detectives were there to meet him instead and took him into custody without incident, police said in a statement.

Farrell was booked into the Santa Clara County Main Jail for four felony charges: child molestation, sexual battery, communicating with a minor with the intent to commit a sex crime, and arranging a meeting with a minor with the intent to commit a sex crime.

Farrell posted $250,000 bail on June 16 and is out of custody, according to Sgt. James Jensen, public information officer for the Santa Clara County Office of the Sheriff.

Farrell is a full-time employee of the Palo Alto Unified School District. He has taught biology and chemistry at Paly since 2012, according to the district, and was made a permanent staff member in the 2014-15 school year. Paly was his first teaching job, according to the district's communications coordinator, Jorge Quintana. Quintana said he believed Farrell "transitioned from the private sector." Quintana later said he had been a senior network administrator with Rockefeller Group Telecommunications Services in New York.

District officials learned of the allegations and of Farrell's arrest on Wednesday evening after being notified by police, Superintendent Max McGee said. Police Chief Dennis Burns called McGee a few times as the incident unfolded.

"I am really appreciative that they reached out to us so quickly and in such detail," McGee said.

The district is immediately putting Farrell on compulsory unpaid leave, McGee said, and will be consulting with an attorney about "any further action that we can legally (take)."

Farrell is not teaching any summer session classes.

McGee said the district has not received any previous complaints about Farrell nor any indication that he engaged in this kind of behavior.

"This was a surprise, I think, to everyone," he told the Weekly.

He added that the district's student-services department and Paly Principal Kim Diorio have been in touch with the student's family.

"What's most important is the well-being of this young lady. I trust that she'll have the support and help of (her) family and certainly of our whole school community," McGee said.

Diorio sent a message about Farrell's arrest to students and parents on Thursday.

"Like you, I was shocked and deeply saddened to first learn of this news," she wrote. "I'm at a loss for words except to say how incredibly saddened I am."

Noting that Farrell is a "well-liked and respected" teacher, Diorio encouraged students to "reach out to your parents, relatives, friends and/or other members of your support network over the coming months, and know that the safety of our students will always remain our number one priority."

She urged parents to "create time and a safe space for our children, especially those who had Mr. Farrell as a teacher, to process and discuss their feelings," particularly given the fact that school is out of session. She said grade-level counselors are available to help students who might need support returning to Paly, and pointed parents to an online list of counseling and crisis resources.

Farrell has a wife and two daughters, according to his Facebook page. He emigrated to the U.S. from Scotland as a teenager, according to an Oct. 11, 2015, profile in Paly's student magazine, Verde.

Farrell described his own teen years during that interview. When asked what advice he would give to his teen self, Farrell was quoted as saying: "Who needs girls? You know? If there was one thing that was rough for me in high school it was I don't think one girl ever looked at me. I think one who was blind actually turned away. It was pretty bad. So if I was to give myself some advice it would be, 'You know what, Ronnie? You're going to do alright in your 20s. Hang in there, buddy. Hang in there.'"

Farrell continued his interview in a lighthearted vein. He said that his most awkward moment as a teen student was his first or second day of high school in America.

"An eraser in Scotland is called a rubber, and I asked my teacher for a rubber in front of the class -- and that was pretty awkward. The whole class kind of just gasped and I was like, 'I made a mistake. I need a rubber,' and that didn't help. And eventually, I figured that out and I never asked for a rubber again, at least from a teacher," he said.

Students gave Farrell overwhelming positive reviews on RateMyTeachers.com, calling him a "terrific" and "funny" teacher who "really knows his material and really cares about his students."

Police said in a statement that detectives are not aware of any additional victims at this time.

Anyone who believes that their child may be a victim is asked to call the police department's 24-hour dispatch center at 650-329-2413. Anyone with information about this incident is also asked to call the dispatch center. Anonymous tips can be emailed to paloalto@tipnow.org or sent by text message or voice mail to 650-383-8984.