MIDLOTHIAN, TX (KTVT/CNN) – Surveillance video was recording when a firefighter took down a would-be robber at a gas station.

A north Texas firefighter is credited with stopping a store robbery.

Bearden – wearing the mask – pushes Daniel Gaskey aside, pulls out a knife, and demands money.

“He’s got a fixed blade knife”, Gaskey recalled thinking.

Gaskey tackled Bearden and pushed him down on the ground, stopping the robbery.

In the video, Bearden, 19, shoved past Gaskey and approached the gas station attendant while holding a knife. “Why are you pushing me out of the way?'” recounted Gaskey, who served as an intelligence Marine from 2003-2011, and deployed to Iraq for nine months in 2005 with 2nd Battalion, 2nd Marine Regiment. He jumped on Bearden’s back, putting him in a headlock and throwing him to the ground.

“I controlled him, I controlled his arms, and I told him, ‘We’re not gonna move til the cops get here”.

“I was like, ‘He’s focused on the lady, I can control this, ‘” Gaskey said.

The police arrive shortly after and take the suspect into custody.

“You know, I honestly could not tell you”, he said about why he acted. “It was just an instinctive reaction”.