CHICAGO — Prosecutors said the man charged in the murder and sexual assault of a 19-year-old University of Illinois at Chicago student was angry she ignored him.

Donald Thurman, 26, was charged with first-degree murder and sexual assault in the death of Ruth George, who was found dead Saturday in a parking garage on the UIC campus.

Judge Charles Beach II ordered Thurman held without bail Tuesday.

George had just returned to campus early Saturday morning before she was attacked. She had just attended a semi-formal event for a co-ed fraternity she belonged to for students interested in a medical profession. She and a friend were dropped off by a Lyft driver. The friend went to her dorm, while George walked by herself to her car. Prosecutors said that’s when Thurman spotted her.

Prosecutors said Thurman thought George was pretty and attempted to talk to her, but she ignored him. He admitted to choking and sexually assaulting George because he “was angry that he was being ignored.”

Surveillance video shows Thurman following George into the UIC parking garage on Halsted and Taylor streets around 1:30 a.m. where prosecutors said he tried to talk to her again. When she continued to ignore him, officials said he put her in a choke hold until she passed out, dragged her into her car and sexually assaulted her in the backseat.

About 35 minutes later, Thurman was seen running from the garage and through campus.

George’s family became concerned when she didn’t return home. Later that Saturday, with the help of UIC police, her family was able to ping her cellphone to the parking lot.

Her sisters were with police when they found her unconscious in the backseat of her car. Cook County Assistant State’s Attorney James Murphy said her sisters attempted to resuscitate her until paramedics arrived, but she was pronounced dead on the scene.

According to the Cook County Medical Examiner, George, of Berwyn, was strangled to death.

Police said they were able to identify Thurman on several surveillance videos, including private and CTA cameras because of a distinctive white jacket he was wearing. They staked out the area to see if he would return, which he did around 2 a.m. Sunday.

Thurman was arrested Sunday and police said he confessed on video to choking and sexually assaulting George.

“The defendant denied that he had sexual intercourse with her but he knew that his DNA would be all over the scene,” Murphy said.

Evidence found at the scene includes, according to prosecutors, a condom that was found on the floor of George’s car, which they said had semen inside.

Prosecutors said Thurman’s palm print was also found on her car.

Thurman was on parole at the time of the alleged attack for an armed robbery in 2016.  He had been sentenced to 6 years, but had been released after only serving two years. His public defender says he has a history of mental health issues and has asked that he be placed in protective custody because he has been receiving death threats.

George’s family has asked for privacy and have not released funeral details.

Her mother released the following statement Tuesday morning:

”Ruth lived out her deep faith in Jesus by loving and serving others, leaving a legacy of Christ-centered kindness and sacrifice.  She was the beloved baby of our family. We grieve with hope. We hold no hatred towards the perpetrator, but our hope is no other girl would be harmed in this way and for a mother to never experience this type of heartache.”

The university’s Center for Student Involvement posted on Facebook about George’s death.

“We are devastated in the wake of the loss of life of one of our student leaders, Ruthie George,” the post said. “During this time of sadness, let us draw together as a UIC family and care for each other. Please keep Ruthie’s family, friends, and her student organization (Delta Epsilon Mu) in your thoughts and prayers.”

Thurman is due back in court on Dec. 16.