Nicolas Martinez
© Collin County Jail/NBC 5 NewsNicolas Francisco Martinez
An off-duty McKinney firefighter and one other person were attacked at the Walmart in Princeton, allegedly by an employee who soon became a former employee. Both victims were taken via CareFlite to the hospital.

The two victims are identified as McKinney Fire Department's Battalion Chief George Cook of Princeton and Frederick Oswald of Princeton. Oswald was reported to be doing contract work for Walmart at the time of the incident. Both victims are out of surgery and are expected to make a full recovery.

The Walmart employee, Nicolas Martinez, 20, allegedly slit the firefighter's throat from behind with about 200-300 shoppers inside the busy store. The horrific incident occurred in front of other customers and workers. The suspect then simply walked out of the store and into a nearby field, where he was arrested.

Martinez was also hurt. Police captured video of officers taking him down on dashcam video.

"When we pulled up on scene the officers ordered him down, while officers did have gunpoint on him not knowing whether he had a gun or knife," said Chief James Waters of the Princeton Police Department.

Erica Jones, Senior Manager of Corporate Communications for Walmart released this statement:
"Today's events are deeply troubling. Our thoughts are with everyone who was a part of this terrible situation. We are thankful to the first responders for their quick action, and we are continuing to work closely with the police. The associate who did this was arrested and his employment at our store was immediately terminated."
The store was locked down and will remain closed until investigation is complete.

Chief Waters was one of three officers seen in the video. The officers responded after helping patrol Dallas streets to allow Dallas officers to attend the funerals of the victims of last week's attack. A Dallas Police officer heading back from the funeral responded to the incident and helped evacuate the store and gather witnesses.

"With our hearts being heavy and seeing everything that's going on there, after we took the suspect into custody we had learned and actually observed one of the Dallas police officers that was actually helping us out," said Waters. "Our professionalism and our professions don't just stop at boundaries, it goes across state lines, it goes across nationwide."

Nicolas Martinez was arraigned on two charges of Aggravated Assault W/Deadly Weapon causing Serious Bodily Injury with a bond amount set at $100,000 each.