DELAWARE COUNTY (WCMH) — A 44-year-old bicyclist died early Sunday morning after being struck by a semi on U.S. 23 in Delaware County while participating in the Ironman Triathlon Race.

Kristen J. Oswald, of Royersford, Pennsylvania, was reportedly struck by a commercial tractor-trailer just before 9 a.m. while riding her bike northbound in the right lane on U.S. 23 near Troutman Road, according to the Ohio State Highway Patrol.

Claude Tremblay, 55, of Sarnia, Ontario, who was driving a Freightliner commercial tractor-trailer northbound on U.S. 23 in the left lane, struck Oswald when Oswald traveled outside the safety zone that had been established for people participating in the event, according to troopers.

A reduced speed zone was in place for motorist on U.S 23, officials said.

Oswald was struck by the semi in the left-hand lane, troopers said.

Oswald, who was wearing a helmet at the time of the crash, was pronounced dead at the scene, according to the Ohio State Highway Patrol.

Oswald’s husband was reportedly still racing when the crash occurred, officials said.

U.S. 23 westbound lanes were closed for three hours while Ohio State Highway Patrol investigated the fatal crash.

A spokesperson for the Ironman event issued the following statement:

“We are deeply saddened to confirm the death of one of our athletes at IRONMAN 70.3 Ohio. Shortly after beginning the bike portion of the race, there was an incident with the athlete and a vehicle. Our condolences go out to the athlete’s family and friends, whom we will continue to support. We are continuing to work with local and state authorities to gather all the details of how this incident occurred and will assist them in any way possible. As this is an ongoing investigation, all further requests should be directed to the authorities.”

Troopers interviewed multiple witnesses at the scene and say the crash remains under investigation.

“You hear of those incidents all the time and you never expect it to happen to you,” said Mario Segura, an athlete from New York. “That’s the worst thing about it, it can happen to anybody. You will never expect it.”

Alexa Rae Hensal, a spectator at the event, offered her thoughts to the victim’s family.

“Just to think about the woman’s family,” she said. “They are waiting on her somewhere and waiting on her and excited to see her. You don’t go into this saying, ‘I may not make it out.’ This should be a fun competition, not a dangerous, life-threatening competition.”

The Ohio State Highway Patrol was assisted at the scene by the Delaware County Sheriff’s Office, Delaware County EMS, Tri-Township Fire and EMS, troopers said.

The Ironman Triathlon Race in Delaware has about 2,600 people participating in the event this year.

PHOTOS FROM THE IRONMAN TRIATHLON RACE

Athletes at the event run, swim and bike at the event.

The competition began at 7 a.m. with a 1.2-mile swim at Delaware State Park.

After leaving the water, athletes climb on bicycles for a 56-mile ride through three counties that will end at Ohio Wesleyan University’s Selby Stadium in Delaware. From there, they will begin a 13.1-mile run back to the stadium.

Click here for more information about Ironman events and courses.

Click here for more information about the Ironman Triathlon Race.