Several school districts in Southern California warned parents this weekend that flutes and recorders given to children through a nonprofit music program may have been contaminated with bodily fluids. At least one district specified that those fluids could have been semen.

Local, state and federal agencies were investigating a male music teacher who visited schools in Southern California through a program called Flutes Across the World, according to updates from the Saugus Union School District, which serves the Santa Clarita area.

“The performer distributes a flutelike musical instrument made of PVC pipe or bamboo to students during a music lesson, and the allegation is that he contaminated some of these instruments with semen,” Saugus Union Superintendent Joan Lucid said in an email to parents on Saturday. “These allegations are deeply concerning, and I realize they raise many questions.”

The California Department of Justice and the U.S. Postal Service were among the agencies investigating the program, the district said. Lucid said children were never alone with the music specialist, who was not a district employee.

The Saugus district urged students who had an instrument from the Flutes Across the World program to place it inside a paper bag and contact the Santa Clarita Valley Sheriff’s Office.

At least 13 school districts in Southern California were potentially affected, the Los Angeles Unified School District said in a statement. LAUSD spokeswoman Shannon Haber said one school in the district may have been involved and that parents there had been notified.

“We will continue to provide updates to our families as they become available,” Haber said. “We are deeply disturbed by these allegations and remain committed to the safety and well-being of all of our students.”

The Fullerton School District sent parents a similar notice Saturday, stating that a presenter from the program — through a partnership with the Orange County Philharmonic Society — had visited two elementary schools in the district over the past academic year, conducting workshops with fourth- through sixth-grade students. The district said the flutes from those programs did not need to be tested or collected, according to local police.

“Although presenters at our schools are never alone with children and are always supervised by a teacher or school staff, in an abundance of caution, this presenter will not return to the Fullerton School District,” the district said. “We were informed that this individual has worked in a number of school districts throughout California and we have no evidence to suggest any of our students are connected with the investigation.”

As word of the investigation spread, CBS Los Angeles reported that many parents felt “sickened” by the news and were returning the potentially contaminated flutes to local law enforcement agencies.

“My kids have brought these flutes home. They’re putting their mouths on it, and they’re playing with these instruments,” Tudy Balta, a parent in the Fountain Valley district, told the news station. “And for someone to contaminate it with their bodily fluids, that’s disgusting. My kids could’ve gotten sick.”

Chantel Uchida, a spokeswoman for the Orange County Philharmonic Society, told the Orange County Register the group had sponsored the Flutes Across the World program in six classrooms in three years. They were one of several arts organizations to sponsor the program, she added — but wouldn’t be doing so anymore.

“We’re so shocked and disgusted,” Uchida told the newspaper. “We will be stepping back from this. There are no plans to continue it in the future.”

It’s unclear what prompted the investigation or how school officials came to suspect that the flutes may have been contaminated. Authorities have not named the subject of the investigation. There was no response to an email to the California attorney general’s office on Sunday.

John Zeretzke, the founder of Flutes Across the World, did not respond to requests for comment Saturday, according to the Associated Press. The website and Facebook account for the group appeared to have been taken down as of Sunday morning. However, a cached version of the site described it as an “international humanitarian organization” in which children make two flutes: one to keep and the other to give to a child elsewhere in the world.

“Each flute is decorated by hand, has a photo tied onto it and inside is placed a personal handwritten note by the flute giver to their unknown flute friend in another part of the world,” the website stated. “They decorate a pair of flutes with symbols of peace, unity and healing. They learn to play music from diverse cultures through listening and watching, the oldest way we learn music and language in the world still today.”

The California-based group said it had, since its founding in 2009, conducted hundreds of workshops with thousands of children in the United States and internationally. It led “Music Missions” in Haiti, the Philippines, Honduras and on Native American reservations, as well as sent “Flute Ambassadors” to Nepal, Africa and Southeast Asia. Flutes Across the World planned on expanding its program to Indonesia this year, the website stated.

A Twitter account for the group remained publicly visible Sunday. Its last tweet was dated Aug. 21 and showed an array of colorfully decorated flutes reportedly sent from the United States to the Philippines.

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