The race director and producer of both the Oasis International Montreal Marathon and Ironman Mont-Tremblant has announced his resignation, three days after a 24-year-old half-marathon participant collapsed and later died.

In his letter of resignation, made public late Wednesday, Dominique Piché wrote that he is leaving the position because of the "unfortunate events" during Sunday's marathon.

The race began 50 minutes late due to a lack of staff to secure the course. Piché publicly apologized for the delay on race day.

Then Patrick Neely, 24, collapsed about two kilometres from the finish line of the 21.1-kilometre race. The Quebec coroner's office has launched an investigation into his death.

According to Radio-Canada sources, an ambulance was requested at least four times before first responders arrived, 25 minutes after Neely passed out.

Radio-Canada has ascertained that the runner collapsed at 9:38 a.m. Urgences-santé says it received the call at 9:55 a.m. First responders then arrived eight minutes later — by which time a full 25 minutes had passed.

Piché wrote that he accepts full responsibility for what happened, saying that his resignation stems from his "desire to be accountable."

The Ironman Group is also the organizer of the Montreal International Marathon. (Al Bello/Getty Images)

The Florida-based Ironman Group, which also owns the Rock'n'Roll Marathon series to which the Montreal marathon belongs, issued a news release Wednesday thanking Piché for his years of service.

On Thursday, there was a new twist in developments, when the group Les événements sportifs Mont-Tremblant issued its own news release, saying it wished to "reaffirm its trust" in Piché's leadership.

"Dominique has shown great skill at organizing a race series that has earned worldwide acclaim. He eagerly shares his passion, thoroughness and savoir-faire, and the event has turned into the huge success it is today," said board chair Patrice Malo in a statement.

"As a result, he will remain executive producer of the IRONMAN 5i50/SPRINT, IRONMAN 70.3 and IRONMAN Mont-Tremblant," Malo said.

The group said Piché will stay on as executive producer of the Mont-Tremblant event but will no longer serve as race director.

Half-Ironman death also rocked triathlon world

Piché, a former Montreal police officer, has been producing sports events for more than 15 years and has been involved with the Canadian Ski Marathon, the Vancouver 2010 Winter Olympics, the Ottawa Marathon and the Montreal Police Bike Tour.

He'd organized the triathlon in Mont-Tremblant, in Quebec's Laurentians, since 2004, and he played a central role in persuading the Ironman Group to expand into eastern Canada in 2012.

Last June, Florida triathlete Jill Levy Morris died during the Ironman Mont-Tremblant 70.3 event.

While race organizers initially posted a brief statement saying she had died "after suffering a medical event" during the race, CBC News reported that 46-year-old Levy Morris had, in fact, died of injuries suffered when she was crushed under the wheels of a support vehicle.

'Sad day for triathlon community'

For many, the loss of Piché as director of the Montreal and Mont-Tremblant events would mark a "really sad day for the triathlon community in Canada."

​Kevin Mackinnon, editor of Triathlon Magazine Canada, said that Piché is "second to none around the world" in terms of what he's done for the sport.

"Dominique was one of these people who was just determined to put on an amazing race and do everything to ensure that the athletes had a fantastic experience," said Mackinnon.

He added that he was saddened to hear of the man's death during the Montreal marathon and suggested that "if stuff went wrong, it was not for lack of preparation and effort."