DENVER -- Police have announced the arrest of a suspect in the December 1997 rape and beating death of University of Colorado senior Susannah Chase.

"The department is ecstatic over this," said Police Chief Mark Beckner.

Detective Chuck Heidel, who had worked the case from the start, broke the news to Chase's mother Friday.

"She is extremely happy, she and her family," Heidel said.

The suspect was identified as Diego Olmos-Alcalde, 38, who was being held on $5 million bond on charges of first-degree murder, second-degree kidnapping and first-degree sex assault.

He appeared in court Monday morning in a blue prison jumpsuit, weeping silently.

"As you might imagine our emotions have run the gamut since we first heard of the DNA match with Susannah's case. We are delighted that a suspect has been identified and apprehended," said a family statement.

Chase, a senior at CU, was walking home alone early on Dec. 21, 1997 after an argument with her boyfriend, when she was raped, beaten with a baseball bat and left for dead in an alley a block from her home.

She died two days later without regaining consciousness.

The case shocked the Boulder community and remained unsolved for 10 years. Police believed the attack was random.

Police never gave up on the case and talked with more than 100 people possibly involved in the death of the 23-year-old from Stamford, Conn. Detectives were pulled off the JonBenet Ramsey homicide investigation to help in the Chase investigation.

In recent years, as forensic science was enhanced, detectives focused on the DNA found in seminal fluid in Chase's body. Investigators had conducted a rape examination within 5 hours after Chase was found and were able to preserve that key DNA evidence.

That DNA matched that of Olmos-Alcalde, whose DNA had been placed on a national registry after he was arrested in Wyoming in 2000 on a kidnapping charge.

Boulder police learned of the match on Thursday.

Olmos-Alcalde failed to report to his Wyoming parole officer and was arrested Saturday morning by Boulder and Aurora police for violating his parole.

In a police interview on Saturday, Olmos-Alcalde was shown a photograph of Chase, and he denied knowing who she was, denied having sex with her and repeatedly denied being involved in Chase's death, according to the arrest affidavit. He also stated he had not been in Boulder since he was 16.

"He repeated these denials several times, even after being told that his DNA had been found on her body," Heidel said.

Police served Olmos-Alcalde with the murder warrant on Sunday, Jan 27.

"What's next for us is a lot of investigation. We have to go back and try to break down where he was in December of '97," said Becker. "Hopefully, this will lead to healing in the community, a sense of satisfaction and ultimately, we hope, a sense of justice."

Tracking Olmos-Alcalde's Steps

As part of their ongoing investigation, Boulder police said Monday that they are trying to find a blue 1979 Datsun 280Z that was driven by Olmos-Alcalde around the time of the chase slaying,

She was killed Dec. 21, 1997. Records indicate the vehicle was sold at auction in Denver in March 1998.

"I believe that there is a strong likelihood that the victim was transported to the final location by vehicle," said Heidel.

The Vehicle Identification Number is HS130111372.

Police issued a photo of a similar looking vehicle but said the shade of blue on the car they are trying to locate may be darker or lighter than the one in the photo.

Anyone with information about this vehicle is asked to contact Detective Fred Patterson at the Boulder Police Detective section at 303-441-3330. Those with information regarding the suspect and who wish to remain anonymous should contact Boulder County Crime Stoppers at 800-222-8477 or 800-444-3776. Tips can also be submitted via the Crime Stoppers Web site at www.crimeshurt.com. Those submitting tips through Crime Stoppers may be eligible for a cash reward of up to $1,000 from Boulder County Crime Stoppers.

Boulder County District Attorney Mary Lacy told 7NEWS she is very excited to get to this point after 10 years.

"It was very surprising, but in a good way," Lacy said.

While she will prosecute the case herself, she said she would not do anything different in this high profile case, including starting with the presumption of innocence.

Olmos-Alcalde Suspected In Several Assault Cases

According to his arrest affidavit, Olmos-Alcalde was, at one time, a suspect in all of these assault cases, involving female victims:

Aug. 10, 2000 in Cheyenne, Wyo.

Jan 1, 1998 in Denver

Jan 16, 1998 in Denver

Feb. 18, 1995 in Union City New Jersey

Olmos-Alcalde was arrested on a charge of first-degree sexual assault in Denver on Jan. 1, 1998, and again two weeks later on the same charge but following a different incident, according to an arrest affidavit.

He was arrested on a charge of criminal sexual contact in Union City, N.J., in 1995, the affidavit said.

Olmos-Alcalde, who is from Chile, went to prison in Wyoming for a kidnapping in 2000 and was released to immigration officials in July 2007, police said.

Investigators were looking into Olmos-Alcalde's immigration status, but he was released from immigration hold because his mother is a citizen.

Heidel said Chase's parents have been supportive throughout the decade-long search for her killer.

"Because the investigation went down a lot of blind alleys, leading to a lot of dead ends, they went down those with us," said Heidel.

Ron Stump, CU vice chancellor for student affairs, said he hoped the arrest would lead to closure in the death of Chase.

"As promised at her memorial, we will continue at CU-Boulder to build, in her memory, a community that strives to eliminate violence in all its forms, but particularly violence against women," he said.

Nurse Talks About Arrest

A Boulder nurse who painstakingly collected evidence ten years ago played a key role in the breaking the case.

Lynn Kimball was working as a nurse at Boulder Community Hospital ten years ago and had extensive training in the Sexual Assault Nurse Examiners Program, S.A.N.E.

“We were on call 24-7, and we had to respond immediately,” said Kimball.

Just a few hours after police found Chase’s body, Kimball conducted the sexual assault exam and found the D.N.A evidence that ultimately led to the arrest of Diego Olmos-Alcalde.

In court Monday, Alcalde sobbed as the judge read the charges against him.

The prompt collection of D.N.A. may help build the case.

The arrest affidavit indicates that “the semen was no older than thirty hours from the time the swabs were taken” and that Chase had had no other sexual partners in that time.

“I felt so relieved,” said Kimball, “Just at the possibility that my examination could have led to a break in the case.”

But she said it is a sad reminder that Boulder County no longer has a S.A.N.E program.

She said most samples are now taken in the emergency room.

“This type of program with S.A.N.E that specifically train nurses to do forensic exams I think is so important, and it really serves the victims well,” she said.