SAN DIEGO -- A Carmel Valley man accused of raping two female UCSD students in their University City homes left behind DNA and other evidence that allowed police to solve the crimes, a prosecutor said Monday.

Teddy Baek, 40, a married father who owned a Kearny Mesa travel agency, was arrested on Dec. 4, 2006, after a third UCSD student working on her computer heard footsteps outside her apartment and called police.

Baek "thought he was invisible" when he stalked two medical students and broke into their apartments late at night, Deputy District Attorney Gretchen Means told jurors in her opening statement at Baek's trial.

However, DNA recovered from the victims matched DNA taken from Baek after his arrest, Means said.

"It took us almost two years to give him a name and a face," she said.

The arrest solved the "Asian Male Smoker Rapist" cases, which had baffled police, the prosecutor said.

Baek assaulted one of the women early on June 13, 2005. The woman had had sex with her boyfriend and had gone to bed around 3 a.m. after he left, Means said.

A short time later, Baek came into her apartment through a bedroom window and put a rag over her mouth, the prosecutor said.

The attacker had a strong odor of cigarettes and an Asian accent, Means said.

The intruder told the woman to be quiet and told her to blindfold herself, the prosecutor said.

"He told her he only wanted her body," Means told the jury.

The assailant told the woman if she did not scream, she wouldn't get hurt, the prosecutor said.

The intruder turned on the light and kissed the woman on her neck and breasts and told her he had heard her earlier and "could not wait," Means said.

Two cigarette butts were also left at the scene, the prosecutor said.

"He left bits and pieces of himself," the prosecutor said.

Nine months later, on March 6, 2006, Baek broke into the apartment of a 24-year-old medical student who had just returned home from the library, Means said.

The woman took a shower and was awakened about 3 a.m. by a male with a strong odor of cigarettes holding a cold metallic object to her, the prosecutor said.

"She was terrified," Means told the jury. "She thought it was a knife."

The woman screamed and struggled as the attacker sexually assaulted her, but he told her "not to make me crazy" and pulled the bed sheets over her head, Means said.

As he did with his other victim, Baek turned on the light and tried to rape the victim, the prosecutor said.

The attacker told the woman he had seen her the night before and felt badly about what had just happened, Means said.

Nine months later, Baek was arrested when the third woman heard footsteps outside her window.

Means said both sexual assault victims were in their early 20s, Asian, and were in UCSD's medical program.

Both attacks happened during finals, in ground-floor apartments, the victims' eyes were bound, the lights were turned on and some sort of latex gloves were used, Means said.

Defense attorney Marc Carlos told the jury it would have to reconcile the fact that prosecutors say Baek is a serial rapist and the Baek who is a father of two and businessman who came to the United States from Korea in 1991 "for the American dream."

Carlos said there are distinct dissimilarities in the two sexual assaults that Baek is accused of committing.

Witness descriptions of the suspect are not consistent, and there was no identification of Baek, the defense attorney told the jury in his opening statement.

One woman said her assailant had a Japanese accent, and there was no weapon used in one of the attacks, Carlos said.

The only thing that was common in the assaults was that the attacker was an Asian man who smoked cigarettes, he said.

In addition, Carlos said Baek's mistress never saw the defendant do anything weird or strange sexually.

Baek bailed out of jail following his arrest and did not flee, Carlos said.

He said the serial rapist series was not solved and a rapist is still at large in the community.

Baek faces multiple life terms in prison if convicted of seven charges, including sexual assault and an allegation that a weapon was used, forcible rape, attempted residential burglary with sexual intent and allegations of multiple victims and tying and binding.