According to charging documents, Santillan on Sept. 4 approached Lonniece Crews as she was parked in outside a hotel on the Northwest Freeway where she was staying after her home flooded.
Santillan allegedly brandished a gun and ordered Crews to get out of the car.
"I just started screaming. I was just in shock - am I really getting robbed now?" Crews told ABC13. "I just started begging for my life and saying, 'I have kids, I have kids. Please don't shoot me!'"
Crews says she heard two shots and got down to cover her 2-year-old son. Police recovered her stolen car two weeks later.
She left her phone in the car, and it was later found at a separate crime scene.
Investigators believe Santillan committed at least two other robberies in the area within an hour.
Anybody with information about his whereabouts is asked to contact police.
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