A now-former security guard at Grandview High School faces multiple charges following allegations he had sexual contact with a student in the back seat of his car after exchanging numerous text messages with her, some of them explicit.

Broderick Lundie, 29, is due in court next Monday on two felony charges: Sexual assault on a child by a person in a position of trust with a victim between 15 and 18 years old, and sexual assault where the age difference between the suspect and victim is 10 years or more.

Lundie was arrested May 4 and later released after posting $25,000 in bail.

Abbe Smith, spokeswoman for Cherry Creek Schools, said Lundie was suspended when the allegations came to light and later resigned.

Marques Ivey, an attorney representing Lundie, declined to comment when reached by 9NEWS.

According to an arrest affidavit obtained by 9Wants to Know, an Aurora police officer was told on April 16 that Lundie was in an “inappropriate relationship” with a Grandview student. Their contacts included the exchange of sexually explicit pictures by text message.

The girl told a detective that she and Lundie began communicating in February and that “it was casual conversation at first but eventually turned more romantic,” according to the affidavit.

The girl described their relationship as “dating.”

Eventually, according to the document, the two traded intimate photographs. That led to a meeting in which Lundie allegedly picked her up at her home, drove to a nearby street and parked.

According to the affidavit, after Lundie was confronted by detectives he “admitted sending nude pictures of himself” to the girl and acknowledged that they met one night and that they had sexual contact – but claimed it was less extensive than what the girl told investigators.

The student acknowledged trading text messages with Lundie. However, when investigators examined her phone they found that more than 16,000 text messages sent to or received from Lundie’s phone had been deleted and, according to the affidavit, it was impossible to recover them. Still, investigators found about 140 images on the girl’s phone that included intimate photos of her as well as pictures of a man believed to be Lundie exposing himself, according to the affidavit.

Lundie was accused of contact with other students – although it is difficult to tell how many because of redactions in the court documents.

Another girl told investigators that she had some contact with Lundie but became uncomfortable and did not respond to messages from him sent over social media.

Contact 9NEWS reporter Kevin Vaughan with tips about this or any story: kevin.vaughan@9news.com or 303-871-1862.