Already linked to the December sexual assault of a woman in Reno, police said Thursday they now have DNA evidence that also ties the suspected abduction of Brianna Denison to an attack in the same neighborhood back in late November.
Police also released a composite sketch of a suspected rapist in a previously unreported attack in the area in October that investigators said is "not inconsistent" with the descriptions in the other three cases.
The developments stem from an "exponential increase" in information flowing into police tip lines since investigators released a description on Monday of a suspect in a December kidnapping and sexual assault also near campus of the University of Nevada, Reno, Reno Police Commander Ron Holladay said.
Police said DNA helped link that crime to evidence collected at the Reno home where the 19-year-old Denison last was seen in the early morning hours of Jan. 20.
On Thursday, Holladay said they now have connected all three attacks with DNA and were investigating the October rape of a woman who came forward on Wednesday to report she was attacked at gunpoint in a UNR parking garage within 100 yards of a campus police station.
UNR Police Chief Adam Garcia said the woman decided to contact authorities as a result of extensive media coverage of Denison's disappearance.
Dennison, 19, a freshman at Santa Barbara City College in California, was last seen in the early morning hours of Jan. 20 at a friend's home near the UNR campus. A Reno High School graduate, she was back home visiting friends and family during winter break.
Police aren't releasing any details on the DNA matchups, but Holladay said the evidence collected at the scene of the November attack included unopened packages of condoms.
In that case, a female victim was battered and sexually groped on Nov. 13, about 6 p.m., Holladay said.
On Dec. 16, another female victim was battered, kidnapped, sexually assaulted and then brought back home by the suspect, he said.
On Jan. 19, the night before Denison last was seen, an unknown suspect returned the home of the victim of the December attack and unsuccessfully attempted to break in, police said.
Police with search dogs and hundreds of volunteers have combed the area daily since Denison's disappearance with no sign of her.
Crime lab technicians earlier determined a small stain on a pillow at the house where Denison vanished is the blood of Denison.
Investigators think someone entered through an unlocked door of the house rented by a Denison friend and three others. Denison, who was sleeping on a couch near a door, was last heard from at 4:20 a.m.