He was an Army veteran living in a South Anchorage home with his wife and working as a technician at a local hospital. But police say Richard Dorsey, 43, is also a serial rapist who held women hostage at knife-point while he brutally assaulted them -- in one case while wearing blue hospital scrubs -- in a string of attacks dating back to 2001.

On Tuesday, Dorsey was charged with rape, attempted murder and assault in cases involving five women. Out on bail awaiting sentencing on a separate sex assault conviction, he was picked up and jailed in Anchorage.

Detectives began piecing the case together earlier this year when Dorsey was on trial for a separate sexual assault in the Carrs Quality Center on Huffman Road from July 2006. In that case, Dorsey stuck his hand up a woman's skirt.

Special Victims Unit Detective Sgt. Ken McCoy found "striking similarities between Dorsey and the unknown suspect in several unsolved sexual assaults" while preparing for that trial, police spokesman Lt. Dave Parker said.

"That's a different scenario, but the brazenness and the boldness of that attack, it was very unusual in the fact that it was so bold," Parker said. "But one of the things that we find, having done sexual assault cases for quite a few years, is that people's behavior tends to amplify over time."

The case got its first big break in March when McCoy spotted Dorsey drinking water from a Styrofoam cup during the trial, according to an affidavit filed in court by Detective Jean Dupuis. Dorsey left the cup on the courtroom table and McCoy seized it as evidence. The DNA from the discarded cup matched that of semen from an unsolved 2002 rape, the affidavit says.

Police say in each of the assaults Dorsey would pull up to a woman along the road and offer her a ride. With the woman in the vehicle, he would drive away to a secluded spot, put a knife to her throat and rape her, according to Dupuis' affidavit. Sometimes he would also rob her of cash when he had finished, police say.

In at least one case, the woman fought him off. On Oct. 13, 2002, Dorsey drove a woman he'd picked up to a spot near the Northern Lights Hotel, then pulled a 6- to 8-inch grooved combat knife and forced her into a portable toilet, the affidavit says. He threatened to kill her and ordered her to get undressed.

"(The victim) described fearing for her life and thinking that the male was going to sexually assault her and then kill her anyways, so she decided to resist and started fighting back," Dupuis wrote. "(The woman) grabbed the knife and was cut during the struggle."

With the woman screaming, the assailant took off and the woman, who was cut and had a broken tooth, flagged down a passing cab for help, the affidavit says. She gave police a description matching Dorsey's and that of his vehicle.

After that case, police say, they received no reports of sex assaults matching the description of Dorsey, his vehicle or his methods until the fall of 2003. Police say Dorsey, during that period, was "laid up" for several months after injuring his right knee in a traffic accident on Oct. 20, 2002.

The first victim, who police say was raped by the same man in 2002 and 2003, did not report the attacks until 2007, according to police. She told police she didn't come forward because she was a prostitute and a drug user, according to Dupuis' affidavit.

But in May 2007, she was walking through the parking lot of the South Anchorage Walmart when she saw the man she said had raped her twice before, court papers say. In both cases, she had been walking along a road, been picked up and then assaulted at knife-point. The second time, she didn't recognize him as the man involved in the first assault until she was in the vehicle and he reached for his knife, the affidavit says.

The woman confronted her alleged rapist in the parking lot and he took off after an exchange of words. She took down the license plate number of Dorsey's maroon Chevy pickup.

In another case, from 2004, police got Dorsey's license plate number from the victim of an attempted sexual assault, Dupuis' affidavit says. The woman told police she got out of Dorsey's truck after an exchange about whether they would have intercourse and he followed her, punched her in the head, then sped off, according to the affidavit.

Dorsey, however, said he was on his way to a NAPA store when he stopped to offer the woman a ride and that he took off after she offered to sell him drugs, according to the affidavit. He denied hitting her and was wasn't charged with a crime. Until now.

"At that time, they didn't have the evidence necessary to charge," Parker said. "However, taken into account with all the other evidence they have and the fact that they were able to develop more (victims) apparently, that's why he's charged with it now."

All together, police say, they were able to link Dorsey to the Carrs assault and five additional victims, though they suspect there may be more. He was convicted of second-degree sexual assault in the Carrs assault in August and was waiting sentencing, police said. He faces 13 new charges including sexual assault, assault and attempted murder. He was booked at the Anchorage jail with bail set at $100,000 cash.

Dorsey, who is from California and transferred to Alaska with the Army in 1997, has been the subject of 18 court cases in Alaska, though most were civil disputes or relatively minor offenses. He was convicted by court-martial in Germany of "weapons violations and larceny" in 1994 and convicted of patronizing a prostitute in Washington in 1997, according to court records.

Dorsey did not yet appear to have an attorney in the new case. His lawyer in the 2006 sex assault case, Chong Yim, did not return a message seeking comment. Dorsey's wife, Gilda Dorsey, declined to comment when reached at home Tuesday evening.