The incident happened at 2:30 a.m. Tuesday inside the 27-year-old victim's building.
Authorities say the suspect, described as a 6-foot tall Hispanic man weighing 170 pounds, followed the woman into the building. He then forced her into an elevator, where he attacked and sexually assaulted her.
Police say the man ran off when the elevator doors opened.
He was last seen wearing a gray shirt, a brown beaded necklace, blue jeans and black sneakers.
Anyone with information in regards to this incident is asked to call Crime Stoppers at 1-800-577-TIPS (8477).
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