A Cherokee High School teacher sexually assaulted one of his students, prosecutors said Wednesday in announcing his arrest on multiple counts of sexual assault, endangering the welfare of a child, and official misconduct.

Brantley Cesanek, 30, of Haddon Township, is accused of having an ongoing sexual relationship with a female student in 2016 and 2017, when she was 16 and 17 years old, prosecutors in Burlington and Camden Counties said. Cesanek was arrested Tuesday.

The alleged victim described sex acts with the defendant that happened on multiple occasions during her junior year and senior year, according to an affidavit of probable cause.

Cesanek admitted that the student stayed over his house twice while she was in high school, but said their sexual relationship did not begin until after she graduated, the affidavit said.

Cesanek taught Latin at Cherokee High School in Marlton and was a mentor for a robotics team there, according to the school district's website. He began teaching there in 2011.

Officials at the Lenape Regional High School District declined to comment because of the ongoing investigation, but provided copies of two emails sent to parents Wednesday.

"As soon as we were made aware of this matter, Mr. Cesanek was not permitted on our grounds or at our events district-wide," superintendent Carol Birnbohm wrote in an email Wednesday afternoon.

Laura Bishop, a spokesperson for the district, said Cesanek had been suspended from his teaching job.

The investigation began when the Burlington County Prosecutor's Office and Evesham Township Police Department received a tip about the alleged relationship. The Camden County Prosecutor's Office joined the investigation when authorities discovered that the alleged sexual assaults took place in Cesanek's home.

Cesanek is being held at the Camden County Correctional Facility awaiting a detention hearing. The investigation is ongoing.

The Burlington County chapter of the New Jersey Education Association office declined to comment.