The Pomfret School in Connecticut has revealed that several of its teachers engaged in improper conduct with students between the 1970s and 2000s, adding its name to a list of elite boarding schools now reckoning with past sexual misconduct by educators.

Pomfret Head of School J. Timothy Richards and board of trustees Chairman Justin P. Klein sent a letter Monday to the school community detailing the results of an independent investigation into the misconduct.

The letter, obtained by The Associated Press, said the investigation found four teachers “more likely than not” engaged in sexual misconduct. One case happened in the early 1970s, one in the 1980s, one spanned the 1980s to early 1990s and the fourth happened after 2000, the report said.

The letter said investigators also received nine other reports involving allegations ranging from boundary violations to sexual misconduct.

“In most of these instances, the investigators found the reports credible, but found that there was insufficient information to complete the investigation or were unable to make a finding by a preponderance of the evidence or concluded that the allegation was unsubstantiated,” the letter said.

The school did not identify the teachers, but it said some received positive recommendations when they left and some are still working with students.

“The school regrets that these letters of support were written for adults who had clearly violated core community standards of behavior,” Richards and Klein wrote.

Karen Schwartzman, a spokeswoman for Pomfret, said they believe two teachers who are alleged to have engaged in sexual misconduct at Pomfret are currently working with children elsewhere.

She said the school told state police but wouldn’t identify the schools where the teachers are working.

In several cases, Pomfret officials were aware of misconduct, but no one reported the allegations to authorities, the letter said. All allegations that should have been reported have now been relayed to the Connecticut Department of Children and Families, Schwartzman said. She did not say how many cases were reported.

Trooper Kelly Grant, a spokeswoman for Connecticut State Police, said there is an active investigation into allegations of past sexual misconduct at the school. She said she did not know how many cases were involved.

Pomfret is just the latest elite boarding school to confront allegations of sexual abuse. An independent report released earlier this month found dozens of students at St. George’s School in Rhode Island were abused by school staff from the 1970s to as recently as 2004.

Pomfret’s head of school, Richards, was previously an administrator at St. George’s and has acknowledged not reporting the 2004 allegations to authorities .

Other schools where abuse has surfaced include Phillips Academy in Andover, Massachusetts , and Phillips Exeter Academy in New Hampshire.

Boarding school tuition at Pomfret is $57,000 per year. The private high school’s alumni include Nobel Prize-winning biochemist James Rothman and Prince Lorenzo Borghese of ABC’s “The Bachelor.”

The letter from Pomfret also noted that an outside attorney had done a comprehensive review of its practices and policies. It says it has a new team to evaluate abuse allegations, and also requires adults and students to undergo training with experts in the field.

“If a matter arises from our student body today or in the future, we are in a much better position to respond,” the letter said. If any new reports emerge, “we will investigate each matter fully, and respond with both empathy and transparency,” the school leaders wrote.

Associated Press writer Michael Melia in Hartford, Connecticut, contributed to this report.

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