Police are searching for a man who tried to sexually assault a woman walking from the Midway Airport Orange Line stop.
It happened around 1 a.m. Monday, in the 4600 block of West 59th Street.
Police say the man threw an 18-year-old woman on the ground and hit her in the head.
He then tried to sexually assault her.
Two people passing by saw the attack, and helped the woman get away.
The attacker is described as being about 5 feet 2 inches tall, and weighing roughly 200 lbs.