A mountain bike rider has died after collapsing on South Mountain Sunday afternoon.
According to the Phoenix Fire Department, crews responded to a report of a 43-year-old man who had suddenly collapsed off of his bike before noon.
Riders and bystanders in the area started and continued CPR efforts until rescuers arrived.
Fire officials say based on how far up the trail the rider was, it was approximately 30 to 40 minutes from the time he collapsed until rescue teams were able to make contact with him.
Crews continued CPR until a cardiac monitor was attached and it was determined that the rider had died.
The rider had no "predicting major medical problems," according to fire officials.
