RENO, Nevada (CNN) -- Candles illuminated the somber faces of hundreds of people who gathered Friday night near the University of Nevada-Reno for a vigil to remember slain college student Brianna Denison.
Mourners sing and pray at a candlelight vigil for Brianna Denison in Reno, Nevada, on Friday.
Students who never knew her joined Denison's friends at the spot on an empty field where her body was found a week earlier 10 miles from the school.
Handwritten posters said "We love you Bri" and "Shine on us Bri."
One of the speakers urged the community to stay vigilant and safe.
"For a brief moment in time, a beautiful young woman graced us with her presence," said Marc Klaas, whose daughter was kidnapped and murdered in 1993.
"But from now on, for all eternity, Reno, Nevada, will have an angel sitting on God's shoulder looking out for your children."
The horror and fear began on a cold winter night last month. A stranger apparently walked into an off-campus house and abducted the sleeping Denison.
She attended Santa Barbara City College in California, but had returned to her hometown of Reno to spend time with friends and family.
Despite the searches and vigils, all hope of a good outcome vanished when Denison's body was discovered.
Police say they believe her killer is responsible for three other sexually motivated attacks in recent months.
As authorities announced that a serial rapist was on the loose, pepper spray began replacing iPods as the hot item on campus at the University of Nevada-Reno. All the local stores are sold out.
Freshman Britany Maxwell now has six canisters of pepper spray, supplied by her mother. She holds one by her side when she walks on campus at night. Watch how students are protecting themselves »
"I carry it with me everywhere," said Maxwell, who no longer feels safe walking alone. "I'm scared. I feel like he could be watching me or my friends at any given moment, deciding to attack again. It's horrible."
The crime stuns Reno Police Detective Lt. Bob McDonald. "I've worked here for 29 years, and I can't remember the last time that we've had a serial rapist that has progressed to the point of abducting a young woman out of a residence and ultimately murdering her," he said.
The hope is that a pair of women's panties could help solve the case. The undergarment, dotted with pink panthers and hearts, was found next to Denison's body.
DNA testing, however, revealed the garment belonged to another woman. It also had traces of DNA from a possible suspect. Police hope the unusual pattern of panthers and hearts may prompt someone to come forward with information.
"We want to get the message out to any potential victims out there that may have lost this underwear during a sexual assault or attack," McDonald said. "They may not be comfortable reporting that, but we will handle it with dignity, and it will remain confidential with us," he added.
Meanwhile, police say it's important that students be vigilant. Many are heeding the warning. Dozens of young college women attended a self-defense class Thursday night conducted by martial arts experts. The university's free shuttle service is receiving a record amount of calls. Fear has become the dominant talk even in the classroom.
"Teachers on a daily basis are stopping class to talk about it; to give us advice on what to do in situations," said junior Christy Griffin. He needs to be caught now. We'll all feel a lot better and safer." E-mail to a friend