Nineteen-year-old Monica Terrones promised she wouldn't let the man get away. Her secret weapon to find the robber was her cellphone, which he was carrying.
"I let him have my phone for a day," Terrones said. "He made calls, stayed on the phone. I was like, ok, went online and called everyone, everyone on it, even if they hung up on me."
Eventually one of the people she dialed fessed up and told her where the suspect was.
Terrones tracked down her car at a gas station, called police, and joined authorities in pursuing the driver.
Her car crashed into a pole, but officers got their guy.
Officers found two Instagram photos of the suspect posing on the stolen car with a gun.