A Serbian competitor in the CrossFit Games died while competing in a swimming event Thursday morning at a Texas lake, officials said.

CrossFit CEO Don Faul said during a news conference that they were 鈥渄eeply saddened鈥� and were working with authorities on the investigation into the death of one of their athletes at Marine Creek Lake in Fort Worth.

The Tarrant County medical examiner鈥檚 office identified the athlete as 28-year-old Lazar Dukic of Serbia. The medical examiner鈥檚 office had not yet listed his cause of death.

An official with the Fort Worth Fire Department said they were called out around 8 a.m. to assist police because there was 鈥渁 participant in the water that was down and hadn鈥檛 been seen in some point in time.鈥�

Officers who were working the event were told a participant was unaccounted for after last being seen in the water and then not resurfacing, police said.

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

Faul said CrossFit had a safety plan and did have safety personnel on site at the event. CrossFit did not respond Thursday to an inquiry from The Associated Press seeking more details on that safety plan.

The Fort Worth Star-Telegram reported the event on Thursday included a 3.5-mile (5.6-kilometer) run followed by an 800-meter (0.5-mile) swim. The newspaper said an estimated 10,000 people were in the area for the games, which began Thursday and were set to run through Sunday.

Kaitlin Pritchard told the newspaper that she was standing by the finish line when she saw Dukic approach. She said he was among swimmers she noticed had changed up their swimming patterns, which she thought could have been because they were tired from the run.

Pritchard saw people she assumed were lifeguards on paddleboards on the lake but didn鈥檛 notice any of them jumped in to try to rescue anyone, she said.

鈥淕auging where the people on the paddleboards were and everything, it鈥檚 just that he should have been reachable,鈥� Pritchard told the newspaper.

Dukic played water polo and was an athlete ambassador for FITAID, a sports drink brand, said Gijs Spaans, general manager for FITAID in Europe. Spaans, who knew Dukic for three years, described him as a driven athlete and a 鈥済uy who walks into a room and lights up the room.鈥�

鈥淗e had an incredible work ethic with his athletics career but, you know, always also made time to speak to people and make time for them,鈥� Spaans said. 鈥淛ust a really, really good dude.鈥�

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.

鈥淚 thought he had this. And then all of a sudden I was thinking, 鈥榃hy is his name not showing up in the finishes?鈥欌�� Spaans said. 鈥淎ll the race, he was in top five of the race. And all of a sudden I see all these other people coming in. I鈥檓 like, 鈥榃hat鈥檚 going on?鈥欌��

鈥淗e was in it to win it,鈥� Spaans added. 鈥淗e was a great swimmer.鈥�

The mission of the CrossFit Games, first held in 2007, is to 鈥渇ind the fittest athletes in the world,鈥� the CrossFit website said. It says the games change every year and often the details are not announced until just before the event.

The CrossFit community is like a family, Faul said.

鈥淲e鈥檙e doing everything in our power during this tragic time to support the family, to support our community,鈥� Faul said.

Dukic鈥檚 biography on the CrossFit website says he was the third-ranked CrossFit athlete in Serbia and the 88th-ranked worldwide. Dukic finished ninth in his debut in the games in 2021, then eighth the next season and ninth in 2023.

Jamie Stengle And Josh Kelety, The Associated Press