At about 5:45 a.m. Saturday, the woman was walking to her apartment in the 14000 block of Vanowen Street when she was confronted by a man trying to speak to her in Spanish, which she does not speak, authorities said. She told police he smelled of alcohol.
The man stepped in front of her and grabbed her, trying to take her pants and underwear off, according to the LAPD.
The man dragged her to the ground, where she fought him for several minutes and was finally able to wrestle free.
The woman kept the struggle in full view of security cameras, which captured the attack, authorities said.
Surveillance video shows another woman walking by and cars slowing down, but police said no one responded to the attack or called 911. As she tried to fight off her attacker, the woman screamed, "Fire! Fire!" to try to get people's attention.
LAPD Capt. Lillian Carranza said that, watching the video, "at one point, you will ... see a lady walking down the street, looking back disturbed by what she's seeing, but at no time did anybody stop to help," CBS Los Angeles reported.
"Even if people don't feel comfortable, necessarily, getting involved physically, there's nothing wrong with standing to the side, dialing 911 to at least make that phone call, and that's all we're asking," LAPD Det. Eric Rose said at a news conference Tuesday.
The suspect is described as a 40- to 45-year-old bald Latino man, with brown eyes, standing about 5-foot-9, according to the LAPD.
Surveillance video showed him walking away after the attack.
"A woman should be able to go and get a cup of coffee in the morning before the sun comes up without being sexually assaulted," LAPD Det. Karen Widman said at the news conference.
Anyone with information about the case has been asked to contact LAPD detectives in Van Nuys at (818) 374-9500. Those who wish to remain anonymous can call the L.A. Regional Crime Stoppers at (800) 222-8477 or visit www.lacrimestoppers.org.