A Missouri mom is crediting the U.S. Constitution's Second Amendment on the right to carry firearms for saving her family from a knife-wielding man who threatened to hurt them.

Katie Claxton said she was in a car with her four children one recent Sunday night while her husband was pumping gas at Rapid Roberts store in Springfield when a man identified by the police as David Middleton who had a large knife approached their vehicle.

"He opened the door and pulled out a knife about the size of a machete and pointed it at me while starting to get in the van," she said.

Claxton then shouted at her husband, "Matt get your gun!" and he pointed the gun at Middleton.

"And the guy stopped getting in the car and said 'You're lucky he has a gun' and then shut the door and started walking away," she wrote on Facebook.

She told the Springfield News Leader that "our Second Amendment right to carry is what saved our lives. If we didn't have our right to carry, I feel like we wouldn't be here today."

She said she called 911 as the man walked away. The family started following the man in their car as he walked down Sunshine Street.

Claxton said Middleton tried but failed to get into some cars parked at a nearby intersection. The police subsequently arrived and arrested him.

Springfield Police Department spokeswoman Lisa Cox confirmed Claxton's story was consistent with the police report that was presented to prosecutors on Monday afternoon.

"You don't go out looking for trouble. But if trouble comes knocking, you're there to answer," Claxton said.

Claxton wrote, "This is why we carry. This is why we need to protect our right to carry."