The mom of a 20-year-old college student who was killed in a hit-and-run at her college campus is fighting for justice.

Florida State University student Elizabeth “Ellie” Sims died on the evening of Monday, April 29, as she was walking home from the library on campus, a GoFundMe created after her death explains.

According to a press release from the Tallahassee Police Department, Sims was using the designated crosswalk at the intersection of Pensacola Street and Lorene Street when she was struck by 18-year-old Willis Trueblood Jr.

“Witnesses and passersby immediately attempted to render life-saving aid to the victim, who sadly succumbed to her injuries on scene,” the press release states.

Trueblood Jr. was located and arrested “less than two hours after the incident” and was charged with leaving the scene of a crash involving death.

According to an arrest/probable cause affidavit reviewed by PEOPLE, Trueblood Jr.’s vehicle had “damage to its hood and windshield consistent with the crash as well as what appeared to be blood and hair in the windshield.”

The court document states that he recalled seeing two vehicles driving in front of him in the left lane that he was going to get into when “boom, just boom, the car, she hit the car.”

He allegedly told officers that he left the scene because he was “panicking” and “didn’t know what to do.” Trueblood Jr. entered a conditional plea of not guilty and has posted bail, according to court records reviewed by PEOPLE.

Following Sims’ death, an anonymous user created a Change.org position urging the installation of a traffic light in the area.

“To many accidents happen due to people driving too fast on a crowded street. We must add stoplights to save lives,” the description of the petition that has acquired nearly 20,000 signatures reads.

Kristen Sims, Ellie’s mother, commented, “My daughter, Ellie, was the girl killed last night. #justice4ellie.”

“There’s just such a hole now that’s left by her absence,” Kristen told Nashville local station WSMV. It’s just such a senseless act. I was literally just here last weekend. I was so proud to be her mother.”

Ellie, a member of the Beta Eta Chapter of the Alpha Chi Omega sorority, was remembered for having an “infectious smile” by her sorority sisters.

“We will forever miss your infectious smile, jamming out while meal prepping in the kitchenette and positive presence that lit up every room. Beta Eta will not be the same without you, but your legacy will live on,” the group shared on Facebook.

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The sorority has also established the Ellie Sims Memorial Fund “to honor Ellie’s life.” The GoFundMe campaign created to help with funeral expenses, has gained over 1,400 donations and has raised over $74,000.