With no suspects and little evidence, police investigating the suspected kidnapping of a young Reno woman appealed again to friends and neighbors to offer up even the most "inconsequential" information they may have about her mysterious disappearance six days ago.

"At this point in time we do not have anything that points to a specific suspect," Reno police commander Ron Holladay told about 150 people who gathered for an update Thursday night at the student union of the University of Nevada, Reno.

Brianna Denison, 19, hasn't been seen since about 4 a.m. on Sunday when she went to sleep on a couch at the home of a friend a few blocks from the UNR campus, about a half-mile from the downtown casino district.

Denison, a freshman at Santa Barbara City College who graduated from Reno High School last spring, was staying with friends who reported her missing about 9 a.m. because her cell phone, purse, shoes and other personal items were left behind.

Police with search dogs have canvassed the neighborhood daily since then. They expanded the effort Thursday to nearby foothills of the Sierra where they'd not looked before and encouraged local residents at the evening forum to continue to come forward with any information that might help find her.

"It is very important," Holladay said. "It is really the little things that may seem inconsequential to you at the time — a person walking in the neighborhood who doesn't belong. A person who hangs out that doesn't go into a residence. A person watching you when you go out."

Police have ruled out as suspects Denison's boyfriend, who reportedly sent her text messages from Oregon in the hours before her disappearance, as well as a man who gave her friend a ride to the home from a Reno casino that early morning.

Holladay said they still were awaiting results of tests on a stain on a pillow on the couch to see if it was blood — as investigators suspect — and whether it matched Denison's type. He said there did not appear to be "any similarities" between the facts surrounding her disappearance and two unsolved cases of sexual attacks on women in the neighborhood in November and December.

Police said earlier Thursday they planned to interview 93 registered sex offenders who live within a mile of the Reno home where Denison last was seen. Holladay said only one of those was a "Tier 1" offender — the most likely to be a threat — and that he had been contacted and ruled out as a suspect.