The 26 year old Crippen died Saturday while competing in the FINA Open Water 10-kilometer World Cup at Fujairah, east of Dubai. He failed to finish and was found in the water two hours later, organizers said.

The president of FINA said Sunday that “overexertion” led to the death of U.S. national team swimmer Fran Crippen at a race in the United Arab Emirates and that the swimming body has launched in investigation into the tragedy.

The winner of the race, Germany’s Thomas Lurz, criticized both FINA and race organizers on Sunday. He said the temperatures were too hot for racing, that FINA’s open water schedule was too grueling and that organizers should have done more to ensure swimmers were safe.

No specific cause of death has been given. Race officials said a medical report and autopsy has been completed but declined to release it to the media at this stage.

FINA rules place no limit on warm water.

“This is usually the case at events in this area,” Marculescu said. “For some athletes it’s good and for some it’s not. Our rules cover only cold water.

“It’s very surprising and unpleasant. This is a swimmer with a lot of experience. He was a fantastic guy and he came from a big swimming family,” Marculescu said. “We’ve never had something like that happen in our sport before. I’m sorry for him and his family.”

Swimmers complained of the warm water temperatures but Ayman Saad, executive director of the UAE swimming association, played down heat as a factor, saying that the water temperature was 84 degrees Fahrenheit (29 degrees Celsius) at the start of the race.

Crippen was the silver medalist in the 10k at the Pan Pacific championships in August, earned a bronze medal in the 10k at the 2009 world championships, was national champion in the 5k in 2009, and won a gold medal in the 10K at the 2007 Pan American Games.

Crippen finished fourth in the 10k and fifth in the 5k at this year’s world championships. He competed in the 2004 U.S. Olympic trials.

On his Facebook page, he posted Thursday that he was “in Dubai for the final World Cup of the season and then off to Italy for vacation!”

The page now has many messages of condolence from friends and fellow swimmers.