The Glendale Fire Department was called out to it's first mountain rescue of the season Saturday morning after receiving 911 calls that a hiker collapsed on a trail on Thunderbird Mountain.
A 53-year-old man wasn't conscious when crews got to him.
The fire department says this is the time of year they start getting more calls like these and a perfect time to remind anyone who plans to hit the trails to take precautions.
Glendale Fire Capt. Linda Rider says the hiker was half a mile up the H-1 trail when he apparently went into cardiac arrest.
"Basically, we are called to the mountain for a patient that was obviously out on the trail, collapsed on the trail," said Rider.
According to the captain, a cardiac nurse was in the area and started CPR immediately.
Firefighters reached the man in less than 10 minutes, their presence alerting other hikers that something was wrong.
The hiking trails in Thunderbird Conservation Park, where the incident happened, are popular.
But even regulars know it's not an easy task reaching the top.
Glendale Fire isn't certain what caused the victim in this case to collapse, but advise for anyone heading out to be careful, especially as the weather heats up.
Take plenty of water and a cell phone and tell someone where you will be.
"If you're going out alone, let someone know where you are and what trail you're going to be on as you can see this was very important because if something happens to you people can make a phone call," said Rider.
Glendale fireFighters were able to use an ATV to get to the man. He was last listed in very critical condition.
Peoria firefighters assisted in this rescue.