It happened on Saturday, Feb. 2 at around 6 a.m.
Police say during the incident, the suspect followed the woman as she was walking through the parking garage.
They say that's when the suspect pointed a gun at her and forced her into his vehicle.
Police say the suspect sexually assaulted the victim and took some of her belongings.
Investigators believe the suspect drove off in a dark grey vehicle.
A forensic sketch artist composed a drawing of the suspect.
Police describe the suspect as a black male, between 5'6" and 5'7" with a thin build and medium brown skin complexion.
Crime Stoppers may pay up to $5,000 for information leading to an arrest.
Information can be reported by calling 713-222-TIPS (8477) or it can be submitted online at www.crime-stoppers.org.
All tipsters remain anonymous.
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