The death of a man in the infield of Texas Motor Speedway on Saturday night during the Sprint Cup Series NRA 500 has been ruled a suicide from a gunshot to the head, according to the Tarrant County Medical Examiner's office.

The incident happened late in the race when Kirk Franklin, 42, of Saginaw, Texas, apparently got into an argument with other campers, according to the Associated Press. Track spokesperson Mike Zizzo said Saturday night that the incident happened "in or around a pickup truck" in the infield.

Firearms were prohibited by Texas law from being brought in to the track by fans. The NRA's sponsorship of the race came under scrutiny when it was announced earlier this year after Michael Waltrip ran a Sandy Hook benefit car at the Daytona 500 encouraging fans to text to give to Newtown, Conn. It was the NRA's first Sprint Cup Series sponsorship; it sponsored the Nationwide Series race at Atlanta Motor Speeedway in September.

As is custom for all race sponsors, the NRA was offered the chance to buy the premium ad package from Fox Sports that would include commercial time, sponsor mentions and graphics with the race name. The NRA declined, and thus the race was presented without a sponsor on in-race graphics and the Fox broadcast mentioned the title sponsor once an hour. Earlier in the week, Connecticut Senator Chris Murphy (D) wrote a letter to Fox to ask the network not to broadcast the race.

The NRA's sponsorship met and passed all NASCAR guidelines for sponsorship approval, but the sanctioning body said on Friday that it would take a closer look at other factors when going through its standard sponsorship approval process moving forward.

In 2008, a fan was hit by a stray bullet at Texas Motor Speedway after a gun was shot into the air and the bullet came into her RV through the roof and landed in her arm.

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