Authorities tell Eyewitness News the man and woman, identified as 33-year-old Christina McCardell, were at a hotel.
While he was inside checking in at the Pearl Inn, McCardell slid over to the driver's seat and sped off in his vehicle.
Police say the man had a gun and when he saw her stealing the truck, he ran out of the lobby and fired at least four shots at her as she drove away.
Woman allegedly steals truck
A bullet hit McCardell in the leg, causing her to lose control and crash into a 63-year-old driver in a Toyota at the intersection of the South Sam Houston Parkway and Bellfort.
The driver, who was on her way to work, was pinned against a light pole.
She and McCardell were taken to the hospital. Both of them are expected to be okay.
Police say McCardell will be charged with auto theft.
RAW VIDEO: Surveillance video shows woman allegedly stealing truck
Surveillance video of shooting
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