She pretended to be the girl’s mother and demanded the woman release her.
"I was basically yelling, 'Let her go,' so as soon as my voice changed, she let her go and Amy walked into my car," the woman said, according to KTRK-TV.
She took the frightened girl to school and called police.
The suspect, identified as Claudia Hernandez Diaz, was arrested and later described as homeless by authorities.
Amy Martinez said the woman who saved her is a “hero.”