**DALLAS, Texas** -- A competitor in the CrossFit Games tragically passed away while participating in a swimming event on Thursday morning at a lake in Texas, officials reported.

CrossFit CEO Don Faul expressed their deep sadness during a news conference and mentioned that they are collaborating with authorities to investigate the death of one of their athletes at Marine Creek Lake in Fort Worth.

The Tarrant County medical examiner's office identified the athlete as 28-year-old Lazar Dukic from Serbia.

The cause of death has not yet been determined by the medical examiner's office.

An official from the Fort Worth Fire Department stated that they received a call around 8 a.

m.

to assist the police because there was a participant in the water who had not been seen for some time.

Officers working at the event were informed that a participant was unaccounted for after being last seen in the water and not resurfacing.

The Fort Worth fire official mentioned that they responded for search and rescue but were not on the scene when the initial call was made.

Faul stated that CrossFit had a safety plan and safety personnel on-site at the event.

CrossFit did not respond to an inquiry from The Associated Press on Thursday seeking more details about the safety plan.

The Fort Worth Star-Telegram reported that the event on Thursday included a 3.

5-mile (5.

6-kilometer) run followed by an 800-meter (0.

5-mile) swim.

The newspaper estimated that around 10,000 people were in the area for the games, which began on Thursday and were set to run through Sunday.

Dukic, who played water polo, was an athlete ambassador for FITAID, a sports drink brand, according to Gijs Spaans, general manager for FITAID in Europe.

Spaans, who had known Dukic for three years, described him as a driven athlete and a person who could light up a room.

He had an incredible work ethic with his athletics career but always made time to speak to people and make time for them, Spaans said.

'Just a really, really good dude.

'Spaans was watching a livestream of the swim miles away at the main event site.

He was looking for Dukic among the swimmers coming out of the water before realizing he was missing.

'I thought he had this.

And then all of a sudden I was thinking, 'Why is his name not showing up in the finishes?'' Spaans said.

'All the race, he was in the top five of the race.

And all of a sudden I see all these other people coming in.

I'm like, 'What's going on?''The mission of the CrossFit Games, first held in 2007, is to 'find the fittest athletes in the world,' according to the CrossFit website.

The games change every year, and often the details are not announced until just before the event.

'We're doing everything in our power during this tragic time to support the family, to support our community,' Faul said.

Dukic's biography on the CrossFit website states that he was the third-ranked CrossFit athlete in Serbia and the 88th-ranked worldwide.

He finished ninth in his debut in the games in 2021, then eighth the next season, and ninth in 2023.