The man charged with murdering a University of Illinois at Chicago student was reportedly “angry that he was being ignored” the morning of the alleged attack, it was revealed Tuesday.

Cook County prosecutors described in grisly detail how 26-year-old Donald Thurman, who was denied bail, trailed freshman Ruth George into a garage and strangled her after she ignored his advances earlier in the day, according to WLS-TV.

“The defendant was angry that he was being ignored,” said Cook County Assistant State’s Attorney James Murphy said at Thurman’s arraignment.

Thurman spotted the student earlier Saturday morning near a campus subway station, The Chicago Tribune reported.

George, who he did not know, ignored his advances, and he became furious.

The prosecutor explained that later inside the Halsted Street Parking Garage, “The defendant came up behind the victim, grabbed her around the neck from behind, and put her into a choke hold.”

Police had said Thurman tailed George into the garage about 1:35 a.m. Saturday. They found George strangled to death in her family car the next morning after her family reported her missing.

“With his arms still wrapped around the victim’s neck, the defendant dragged the victim from the ground and he opened her back seat car door,” Murphy said at Tuesday’s hearing.

Thurman sexually assaulted George when she was already unconscious, prosecutors allege.

Investigators linked him to the crime with a palm print and DNA evidence found at the scene, the report said.

Cops said Thurman confessed to the brutal crime after they tracked him down at a nearby subway station with the help of garage surveillance footage.