RENO - Police said they plan to interview about 100 registered sex offenders who live within a mile of the Reno home where a college student mysteriously vanished five days ago.
Reno police spokesman Steve Frady said Thursday the questioning was a routine part of the investigation into the case of Brianna Denison, 19, who was last seen sleeping on a couch at a friend's house near the University of Nevada, Reno campus.
"It's something that's done in cases like this," Frady said. "Police detectives are covering every aspect to try to obtain any new leads that can help bring Brianna safely home to her family."
All of the more than 1,700 registered sex offenders in Washoe County around Reno will be contacted as part of the investigation, he added.
Police stressed that the number of offenders living near campus is low compared with the rest of the county. The offenders, convicted of all levels of sex crimes, are regularly monitored by the police department.
Police also continue to investigate two attacks on UNR female students late last year in an effort to determine whether there's a link between them and Denison's disappearance.
The previous cases, involving an abduction and rape in December and a fondling in November, also occurred near the campus.
"At this time, the other two cases do not appear to be related to her disappearance," Frady said. "However, we're not ruling out that possibility."
Denison's mother and aunt asked for people to keep their eyes open, saying Brianna was responsible and serious about her college career.
"We know that someone will see her and that they will get her back to us," said Lauren Denison, the teen's aunt, on NBC's "Today" show Thursday.
Police questioned a man who gave a ride home to Denison's friend the night Denison disappeared from the home near the UNR campus, but investigators said he is not a suspect.
"Basically, Brianna has disappeared. She has fallen off the face of the Earth," said Adam Garcia, campus police chief at UNR.
Denison was last seen at 4 a.m. Sunday. Police said she was sleeping near an unlocked glass door after a night of partying. When her friends awoke, she was gone - but her clothes, purse and cell phone were left behind.
"All the indicators are that Brianna has been abducted. It is our sincere hope that she'll come walking in the door any minute, but the longer it goes, the less the chances are of that occurring," said Ron Holladay, a Reno police commander.
Detectives were awaiting test results on whether a silver dollar-sized stain on the pillow Denison was using is blood.
Denison, a Reno native, was home for winter break from Santa Barbara City College in Santa Barbara, Calif., where she is a student.
You can help
If you have any information about Brianna Denison or can provide investigators with any help in relation to this case, cal the 24-hour tip line set up by Reno police: 745-3521.