LAS VEGAS (KLAS) -- The family of a UNLV student who died after a fraternity boxing match is demanding answers.

The I-Team has learned that Nathan Valencia collapsed after the fight ended on November 19th.  He passed away four days later. 

His family told the I-Team he suffered brain injuries which he could not recover from.  

“We will leave no stone unturned to determine how a 20-year-old ended up in a school-sanctioned amateur fight that cost him his life,” the family wrote in a statement sent through their attorneys, Nick Lasso and Ryan Zimmer of the Richard Harris Law Firm.

“I was like this, this thing, it’s like an underground fight club,” Joe Castro said. 

He told the I-Team that he is a longtime friend of Valencia’s. 

Castro said Valencia did not have boxing experience but wanted to participate in the charity event as a member of his fraternity, Sigma Alpha Epsilon. 

Kappa Sigma Fraternity held the event at Sahara Event Center, 800 E. Karen in Las Vegas.

According to social media posts, proceeds from the boxing event were to go to Center Ring Boxing.

Valencia’s parents told the I-Team that they believe there was no professional referee or immediate medical help.  “I saw no medical, no doctors, nothing,” Castro said.

He also told the I-Team that after Nathan collapsed, a brawl broke out.  “…members there about doing their own thing while Nathan was just in the ring like laying there,” Castro said.  “It was ridiculous.”

The I-Team showed a video of the fight to Hall of Fame boxing referee Richard Steele. 

He pointed out how Nathan turned his back during the fight.  “Anytime I see a fighter turn away from the fight, the fight is over,” Steele said. 

When asked whether the individual in the ring appeared to be a professional referee, Steele said no.  “He wasn’t in the right position most of the time,” he said. 

Steele also told the I-Team that there are rules in place for events like the November 19th boxing match.  “You got to have an ambulance. You got to have a professional doctor,” he said. 

Steele added that he believes while the crowd was cheering, Valencia was receiving what turned out to be fatal punches.

“To lose someone so precious like that, it’s hard,” Xavier De La Rosa told the I-Team.  He knew Valencia since they were students at Bishop Gorman High School. 

“It should have been done correctly.  It shouldn’t have been overlooked,” said La Rosa

The family’s attorney told the I-Team that Metro Police are investigating the incident.

The family's full statement sent through their attorneys is provided below.

The Valencia family is heartbroken over the loss of Nathan. Our preliminary investigation reveals mistakes were made and safety precautions overlooked.

We will be completing a full investigation to determine how UNLV and the Kappa Sigma Fraternity could allow and promote an event like this to take place. 

College students should not be placed in a situation where they are pitted against each other for combat.  “Kappa Sigma Fight Night” is an event that has been held annually and was well known to both UNLV and the national Kappa Sigma Fraternity. 

We will leave no stone unturned to determine how a 20 year old ended up in a school-sanctioned amateur fight that cost him his life. The family has asked for privacy during this time to grieve.

Nick Lasso & Ryan Zimmer of the Richard Harris Law Firm (Valencia family attornies)

The I-Team reached out to Kappa Sigma Fraternity, their statement is provided below.

Kappa Sigma Fraternity is greatly saddened by the loss of Nathan Valencia at the University of Nevada, Las Vegas. Our deepest condolences, thoughts and prayers are with the Valencia family and the entire UNLV community.

Kappa Sigma Fraternity

The I-Team also reached out to Sahara Event Center which sent the following statement provided below.

Statement from Sahara Event Center

We are deeply saddened by the  death of Nathan Valencia, we want to extend our deepest condolences to his family, as our thoughts are with him & his family & the entire UNLV community at this time of grief.

Sahara Event Center

The day after the I-Team first reported on Valencia’s death, UNLV President Richard Whitfield sent the following email to the university community.

Dear Campus,

It is with a heavy heart and profound sadness I share that a member of the UNLV family is no longer with us.

Nathan Tyler Valencia has passed away following a tragic incident a week ago. Nathan was a junior at UNLV and had participated in Kappa Sigma Fraternity’s “Fight Night,” an off-campus event intended to raise money.

Soon after his fight, Nathan collapsed and was taken to a hospital. We are shocked and heartbroken as we mourn the loss of one of our own.

Coping with the loss of life is always difficult, especially under these circumstances.

UNLV is committing all available resources to review the incident and determine how off-campus events like these can be as safe as possible. 

Our deepest sympathies go out to his family, friends, and loved ones. I am sure words cannot describe their feeling of grief and emptiness. They are in our thoughts during this very difficult time. The Rebel community shares their loss.

Warmest regards,

Keith Whitfield, UNLV President

There is a GoFundMe account set up to help the family with medical and funeral expenses.

A candlelight vigil will be held on Saturday, Nov. 27 to honor Nathan Valencia’s memory.

More information about the vigil is listed below.