NEW YORK (CBSNewYork/AP) — Some Brooklyn Technical High School students are speaking out after a teacher accused of sending an explicit photograph to a student was charged with 36 additional counts alleging he victimized six others.

Sean Shaynak, 44, was still in custody Wednesday after he pleaded not guilty Tuesday to the new charges.

He was in court for allegedly sending a nude picture of himself to a 16-year-old female student when police charged him with the 36 new counts, including kidnapping, forcible touching, sexual abuse and criminal sexual act.

A judge set bail at $750,000 bond or $500,000 cash. Bail was also set at $250,000 for the previous charge. He pleaded not guilty in August to charges that included dissemination of indecent material to a minor.

Investigators seized three computers and two phones and discovered thousands of text messages, as well as hundreds of photographs and videos, after the East Flatbush man’s Aug. 26 arrest, according to prosecutors.

An investigation revealed that Shaynak had allegedly victimized six teenage girls, ranging in age from 13 to 19, between 2011 and 2014, prosecutors said.

“It is shocking that a public high school teacher allegedly sexually preyed on vulnerable students,” Kings County District Attorney Kenneth Thompson said. “We will now seek to vindicate the rights of those students.”

“It’s disgusting,” said Mayor Bill de Blasio, whose son, Dante, attends Brooklyn Tech. “This is someone who clearly should not have been a teacher, and I guarantee you he will never teach in a classroom again. And it’s absolutely unacceptable, and he will suffer plenty of consequences for it.”

Prosecutors allege Shaynak asked two girls to have sex with each other, took a 15-year-old student to a nude beach in New Jersey without her parents’ consent, sent explicit photos to four students, inappropriately touched and kissed students and gave alcohol and cigarettes to minors.

As CBS 2’s Weijia Jiang reported, Shaynak has also been accused of bringing a teenager to an out of state gay club where she watched him with other men.

Shaynak is also charged with reckless endangerment and menacing for allegedly terrorizing a former student with whom he had a prior relationship, prosecutors said.

Many students Wednesday morning were disturbed to hear about the allegations.

“You look up to your teachers, sometimes even see like a parent figure,” student Nicole Ilizaroe told CBS 2’s Weijia Jiang. “So it’s scary that could happen.”

“You couldn’t really tell that he would do any of that stuff,” another student said.

Others said they weren’t surprised.

“He was basically a teenager that taught here,” one student said. “He did everything that a teenager would do.”

Department of Education spokeswoman Devora Kaye released a statement saying, “These alleged actions are completely unacceptable and have no place in, or outside of, our schools.

“The DOE took swift action to immediately reassign Mr. Shaynak following his initial arrest,” Kaye said. “He is not, and will not be, in contact with students. Student safety remains our top priority.”

Thompson didn’t offer any specifics, but said the investigation into the case is not finished.

“We’re going to continue this investigation to make sure that there’s no other victim out there, so no way is this over,” he told WCBS 880’s Paul Murnane. “This is just the beginning.”

If convicted, Shaynak faces up to 25 years on the top charge.

The New York Times, citing court documents and interviews, reported Wednesday that Shaynak beat up an 11-year-old boy in 2005 in Maryland, four years before being hired at Brooklyn Tech. Shaynak allegedly tried to choke his young neighbor, threw him to the ground and punched him in the head and face repeatedly.

The boy’s family tried to press charges, but Shaynak was never convicted of any crime in the case, the Times reported.

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