Watch Video: Alcatraz Triathlon Turns Harrowing

An Austin, Texas man died after plunging into cold waters around Alcatraz for a swim across the San Francisco Bay on Sunday as part of the Escape from Alcatraz Triathlon.

His death cast a shadow over the normally boisterous display of athletic endurance.

In this video, a call for help from an unidentified swimmer brings a rescue boat.

More details about the death emerged on Monday, reported by the Contra Costa Times:

SAN FRANCISCO -- A triathlete who died Sunday morning during the swimming portion of Escape from Alcratraz Triathlon has been identified as 46-year-old Ross Ehilinger of Austin, Texas.

Ehilinger suffered a heart attack about 7:30 a.m. after entering the water for the 1.5-mile swimming portion of the race, according to the San Francisco medical examiner's office. He was the first competitor in the 33-year-history of the race to die during the competition.

Here are more photos and video from the event:

http://storify.com/kqednews/escape-from-alcatraz-triathalon

Here are the details of the race from The Associated Press:

SAN FRANCISCO (AP) — A 46-year-old Texas man died of an apparent heart attack Sunday in the frigid waters of the San Francisco Bay just moments after the start of the Escape From Alcatraz Triathlon, race officials said.

"We have reason to believe the gentleman suffered from a massive cardiac event as he entered the water and began the swim," race officials said in a statement.

The race was held three months earlier than previous years and in far colder waters, but organizers said the temperature did not contribute to the death.

"Was it colder than normal? Yes. But in my opinion, the water temperature was not a factor at all in this tragedy," Bill Burke, the race's director, told the San Francisco Chronicle. "The gentleman obviously had a heart condition he was unaware of."

Organizers said the death was the first in the 33-year history of the event, which begins with a 1.5-mile swim from the island home of the former federal prison. The swimming portion is followed by an 18-mile bike ride and an 8-mile run through Golden Gate Park and along the San Francisco coast.

The race had participants from around the world ranging from 13 to 80 years old. The winner was Javier Gomez of Spain.

The triathlon's water safety team noticed the man in distress shortly after the 7:30 a.m. start of the race, the statement said. They performed CPR while pulling him to shore and after reaching land, but he could not be revived.

The unidentified man from Austin was pulled from the water and CPR was performed, but he could not be revived.

"What happened today was very, very sad," Burke said. "It underscores that athletes need to be checked carefully by a cardiologist before pushing themselves."