July 20 (Bloomberg) -- An unidentified 32-year-old man died today after being pulled unconscious from the Hudson River during the first stage of the New York City Triathlon.

The man was three-quarters of the way into the 0.93 mile (1.5 kilometers) swim when several swimmers spotted him in distress and motioned for nearby boats monitoring the race to come to his aid, Bill Burke, race director, said in a telephone interview.

Rescuers drove to the end of the swim section while trying to revive him. He was taken away in an ambulance and later pronounced dead at St. Luke's Roosevelt Hospital Center. Burke declined to identify the man because his family in Argentina hadn't been notified yet.

The death was the first in the event's eight-year history, which had 3,000 competitors from 30 countries today. Burke wasn't sure how long the man, who was pulled from the river shortly before 8 a.m., had been in the water before rescuers responded. The swim is followed by a 24.9-mile bicycle ride and a 6.2-mile run.

The New York City area was under a ``heat advisory'' during the competition and several other racers were treated for heat- related illnesses, Burke said.

Swimmers reported being stung by jellyfish during the race. Burke wasn't aware of anyone suffering an allergic reaction to a jellyfish sting.

An autopsy to determine the cause of death is planned for tomorrow, Ellen Borakove, a spokeswoman for the city medical examiner, told the New York Times.

To contact the reporter on this story: Larry DiTore in New York at lditore@bloomberg.net

Last Updated: July 20, 2008 20:57 EDT