BOULDER, Colo. -- A 20-year-old University of Colorado student has been cited for false reporting after Boulder police say she fabricated a story about fighting off a knife-wielding black man last weekend.

Nina Fiorillo was issued a summons for false reporting on Thursday afternoon, police spokeswoman Kim Kobel said. False reporting to authorities is a misdemeanor carrying a maximum penalty of six months in jail and a $750 fine.

The woman told police she was walking alone in the 1100 block of University Avenue in The Hill neighborhood just after midnight Sunday when she was grabbed from behind by a man.

"She reported that the man had a knife, but that she was able to free herself after a short struggle," Kobel said. "She claimed the man had scratched her forearms, possibly with the knife. But otherwise, she was unhurt."

Police said the woman made up a detailed description of that attacker, saying he was a black man, who was about 24 years old, stood 5-feet 11-inches to 6-feet tall and weighed about 200 pounds. She said he was wearing a dark-colored zip-up sweatshirt or jacket.

"While being interviewed for further details, Fiorillo admitted to detectives that she made up the story and the attack never occurred," Kobel said.

The bogus attack claim caused the University of Colorado to send out an email alert Sunday, warning students about the reported attack and reminding them to take safety precautions.

Police did not say why the woman would make up the report.