A New Jersey substitute teacher is reportedly accused of sexually assaulting a male student in addition to allegedly sending him sexually explicit messages online
Credit: Union County Sheriff's Office

A New Jersey substitute middle school teacher is accused of sexually assaulting a male student in addition to allegedly sending him sexually explicit messages online, the Associated Press, CBS News and NJ.com report.

Nataly Lopez, 27, has been charged with first-degree aggravated sexual assault, second-degree sexual assault and third-degree endangering the welfare of a child, the Union County, New Jersey, Sheriff’s Office said in a statement obtained by CBS News.

She allegedly had sex with the student in her car at least twice and exchanged messages with him for weeks, according to the AP.

Lopez taught in Elizabeth, New Jersey, but was not an employee of the school district there, according to these reports. Instead she worked for Source4Teachers, a third-party company that staffed substitute teachers for the district.

The age of the student involved has not been released. Law enforcement could not immediately be reached for comment on Monday.

According to a criminal complaint obtained by PEOPLE, the student was between 13 and 16 years old during the alleged sexual assaults, which police claim occurred between May 1 and June 21.

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CBS News reports that Lopez was arrested without incident at her home on Thursday afternoon and is being held in the Union County Jail.

In a statement to PEOPLE, Elizabeth Schools Superintendent Olga Hugelmeyer said the district banned Lopez from entering its schools as soon as they became aware of the allegations against her.

“Law enforcement and social service agencies were notified as was the substitute’s employer,” Hugelmeyer said. “The safety of our children is always the Elizabeth Schools’ top priority,” she said.

According to NJ.com, Source4Teachers said in its own statement that Lopez had been blocked from working with client school districts until police have finished investigating.

Lopez underwent both state and federal background checks as part of her employment, the company said, NJ.com reports. Her “background checks … showed no previous history of any illegal or inappropriate action,” the company said.

Lopez pleaded not guilty to her charges on Friday. She remains in custody and a detention hearing is scheduled for Wednesday, according to court officials.

It is unclear if she has retained an attorney who could comment on her behalf.

A Source4Teachers spokesman was unavailable for comment on Monday.