Officials closed a rural Oklahoma school system this week after the sheriff began investigating online threats against a transgender student.

Bryan County Sheriff Johnny Christian said Tuesday his office started investigating over the weekend after adults made threatening comments on Facebook about a 12-year-old transgender girl using the girls’ bathroom at Achille Public Schools, about 160 miles southeast of Oklahoma City and near the Texas border.

A number of the threats involved physical violence, including one that said: “If he wants to be a female, make him a female. A good sharp knife will do the job really quick,” NBC affiliate KFOR reported.

School officials arranged for the student to use a staff bathroom when she was in elementary school, but she was in an unfamiliar building since it was her first week of middle school, Sheriff Christian said.

The sheriff said no arrests have been made, but the child’s mother sought a protective order against a man who confronted the woman in person. Christian said about 20 teens and young adults gathered Tuesday for a small rally in support of the transgender girl.

The sheriff has also contacted the FBI to help investigate the threats.

“A lot of the negative comments and what we perceived as threats were outside our county and, sometimes, out-of-state,” Christian said. But he added that the man who provoked the child’s mother lived in town.

Achille Superintendent Rick Beene said the Facebook page where the threatening comments were posted, “Achille ISD Parent Group,” is not officially tied to the school district, and he said most of the people who participated in the threatening conversation do not reside in the district.

“Our kids, our parents, most of our community is very, very good people ... very open to all ethnicities, all populations and, really, we’ve got a group of kids that love each other,” Beene told KFOR.

Beene said the district is open to new resources for training when it comes to accommodating transgender students.

"I need education; we all need to be educated,” he said. “It’s certainly something that people didn’t deal with 20, 30 years ago.”

Classes began Aug. 8, but were canceled Monday and Tuesday after the sheriff started investigating and demonstrations were expected. Schools are scheduled to reopen Wednesday.

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