FORT WORTH, Texas -- Thursday morning's trip to Wal-Mart at the corner of Hulen Street and Oakmont Boulevard didn't end how Samantha Herrera expected.

"It was crazy. I'm still shaken up from it," said Herrera.

While she and her mother were about to leave the parking lot just after 11 a.m., they noticed an older woman that looked scared. She flagged them down for help.

"She said a man had just grabbed her wallet," said Herrera.

Mother and daughter started driving around the parking lot looking for the man. Samantha started recording with her cell phone just in case they could catch a picture of him.

Turns out, she did more than that.

"We saw him by the Wendy's, so we pulled up and I just decided to get him," she said. "I told him, 'You're not getting away, you're not.' This [the victim] is somebody's grandmother."

She ended up tackling 60-year-old Bobby Montgomery to the ground and held him there until Fort Worth police arrived on scene to make an arrest.

The woman victim told Samantha she was the store to buy dinners for a local Thanksgiving effort to help feed the less fortunate at Saint Andrew Catholic Church.

"The lady cop just told me, 'Pound it. Good job.' She doesn't see this often: ladies chasing guys down," said Herrera.

Montgomery was booked into jail on a theft charge.

Herrera says she was just glad to help.