MEXIA (CBSDFW.COM) – Shot and killed after a Dallas Cowboys game at AT&T Stadium, the family of Rick Sells is questioning the security after the game and wonder if his death was preventable.

“It makes me sick and disgusted that it was allowed to continue to the point of my brother’s life,” said Victoria Gunning, the victim’s sister.

Gunning does not understand why the same man who Arlington Police believe killed her brother, had a gun and was not stopped by security after starting two fights before pulling the trigger.

“They need to have enough security for all of the people that are there,” said Gunning.

Sells was shot in the neck according to investigators after he tried to break up a fight between two other men. Gunning believes there should have been more security around to help stop such violence.

“I think that my brother might have had a chance,” said Gunning.

Lawyer Chris Hamilton, who is familiar with liability cases, said someone needs to look at a timeline of events, the amount of security in place and what the Cowboys and AT&T Stadium do to stop acts of violence.

“If I were a member of this family, I would want to aggressively investigate to get to the bottom of what happened,” said Hamilton.

Arlington Police released a statement writing that it has a, “robust security plan” and “believe this was an isolated incident.”

When the Dallas Cowboys were reached for comment on the situation, a spokesperson released a statement on behalf of AT&T Stadium.

“At this time our thoughts and prayers go out to the family and friends of Mr. Sells on this very sad loss of a loved one. The security and safety of our patrons is our number one priority, and our partnership with the Arlington Police Department has always been very strong in that regard. As always, we will continue to work closely with the Arlington Police Department to do everything possible to help ensure a safe experience for all of our visitors.

The Arlington Police had an immediate response to this incident—which did not occur in a stadium parking lot. To the best of our knowledge the accused was not a ticket holder to the game that evening.”

Arlington Police said it does no plan to make any changes to the current security plan.

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