JOLIET (CBS) — A Joliet Central High School teacher resigned Friday after the district investigated a rumor alleging he had sexual affairs with students.

Students had been talking on Twitter about the allegations of a teacher having sex with girls.

“We are aware of rumors and are investigating the matter. Personnel issues are confidential,” district spokeswoman Kristine Schlismann said Friday.

The alleged sexual contact occurred outside of Joliet, so police gave the case to the Will County Sheriff’s Department.

The case is still under investigation and no one has been arrested or charged with any crime.

“Upon receiving information about alleged misconduct by a staff member, we immediately commenced an investigation. As a result of the investigation, the teacher has resigned,” Schlismann said.

“I am very shocked and disappointed about this matter,” school board President Jeff Pierson said.

On Monday night, the district sent a message to all students’ parents and guardians via an automated phone messenger system informing them about the alleged misconduct with students and the teacher’s resignation.

“To the extent possible, we have spoken to any students who may have been involved. These students’ parents or guardians have been contacted. Joliet Central High School will have additional support services available for students who may need to share their emotions. Counselors and social workers will be available o speak with students,” the message said. “We encourage you to maintain an open line of communication with your student. If your child has relevant information, please contact the Will County Sheriff’s Office or have your student speak to a trusted adult.”

The board is expected to accept the teacher’s resignation at its special meeting at 5:30 p.m. Wednesday.

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