A man died after collapsing from his bike on a South Mountain trail Sunday.
Phoenix and Tempe Fire Departments responded to a call just before noon.
Some bikers and witnesses in the area assisted the man by giving him CPR until the emergency responders arrived.
Based on how far up the trail the man was, it was approximately 30-40 minutes from the time he collapsed until Phoenix Fire Mountain Rescue Teams were able to make contact, according to Phoenix Fire Department.
While on scene, medical responders continued CPR until a cardiac monitor determined that the man had died.
The biker was a 43-year-old man who no predicting major medical problems, Phoenix fire said.
The area is closed for investigation.