Investigators say the suspect threw the woman to the ground, hit her on the head and tried to rape her.
Chicago police issued a community alert Friday morning about a violent and bold attack that happened on Monday at 1 a.m.
"My parents are always telling me that I shouldn't take the bus late, so that's definitely always a precaution that I've always been told to take. It's not safe out here," said Sasha Reyes, CTA rider.
The victim is an 18-year-old woman who was leaving the Midway Orange Line train and bus stop, an area with cameras, security and plenty of people in and out. The assault happened near the station.
"You see all the security people around, you think it'd be pretty safe and somebody would be pretty much keeping an eye on everybody, but you never know," said Annette Faz, CTA Rider
The teenager was hit on the head and pushed to the ground. The suspect, police say, tried to sexually assault her but two unidentified people stepped in and chased off the attacker.
I'm glad, I'm actually satisfied that people actually started to step up because that's happening more and more in different communities. I hope she's OK, honestly, and its kind of sad that it had to happen, at the same time," said Cierrah Dixon, CTA Rider.
Police describe the suspect as a white or Hispanic male, 20-25 years old, 5'5, 200 pounds, short brown hair, brown eyes, wearing a red baseball cap, red shirt and blue pants.
There is no word yet if CTA cameras at the train stop entrance captured any images of the attacker. Police are still looking for the suspect and are reminding women to walk in pairs and stay in well-lit areas.