Lily Paxson was near Richmond and Chimney Rock before 1 p.m. on Thursday when she noticed a man approach the young woman on the sidewalk from behind.
She said at first it seemed like he was trying to pet the dog, but then he grabbed her.
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"Her body language seemed that all she wanted to do was get away from him," Paxson recalled. "She was fighting him off of her, then he started hitting her and kicking the dog, grabbing her and lifting her up."
She said things got "violent and aggressive" quickly.
In a state of disbelief, Paxson said she rolled down her windows, started screaming and honking her horn.
Shortly after, three men got out of their cars and intervened.
"Some had guns, and at that point in time, it really became a cross between the Wild West and Gotham City," Paxson recalled.
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Paxson called 911 as she drove away for her own safety.
"One of the good guys separated the girl and the dog and they seemed like they were OK and safe," Paxson said.
Houston Police said their officers responded to the area shortly after but were not able to speak with anyone involved.
ABC13 has not been able to confirm if the two knew one another.
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