A California man collapsed and died during the Boney Mountain Half Marathon on May 10 amid high temperatures. Spencer Cabral, 38, was airlifted to a nearby hospital where he was pronounced dead, according to several news reports.

First responders from the Ventura Fire Department found three other runners suffering from heat-related illnesses and took them to the hospital separately. On May 10, the day of the Boney Mountain Half Marathon, the National Weather Service issued a heat advisory. The race started at 8 a.m., and temperatures were already spiking — the Los Angeles Daily News reported temps reaching 103 degrees.

The Boney Half Marathon is run by SoCalTrail Events and held in Thousand Oaks, Calif. According to the event website, the course takes runners “deep within Sycamore Canyon featuring multiple creek crossings under Boney Mountain’s boulderous peaks.”

Cabral’s wife, Vanessa, was reportedly watching his progress on a tracker. But when he didn’t finish with other racers, she notified organizers that something might be wrong. They informed her at that time that he’d already been airlifted to the hospital. According to VCStar, she has not heard from the race organizers since.

“We are deeply saddened by the tragic loss of Spencer Cabral,” an official statement from SoCalTrail read. “Our hearts go out to his family and loved ones during this incredibly difficult time. The entire trail running community is grieving alongside them.”

Numerous Victims & Quick Response

According to Andy VanSciever, a spokesperson for the Ventura County Fire Department, the first 911 call was received at 11:12 a.m.

VanSciever told GearJunkie that the fire department responded quickly, dispatching a helicopter, fire engine, and four ambulances. At first, they were only aware of one victim. But as more victims were found, two additional ambulances were called, and Division Chief Tony Occhipinti declared a mass casualty incident.

The last victim was taken to Simi Valley Hospital at 12:34, VanSciever said.

“It’s pretty tragic that one person succumbed to their injuries after they were transported,” VanSciever said. “But any time we can get there quickly and do some interventions, it’s better for the outcome.”

The Ventura County Medical Examiner’s Office has not yet released Cabral’s cause of death.

Stay Hydrated, Go Prepared

In its statement, SoCalTrail said that it plans all of its events with its medical director, and deploys experienced medical staff and search and rescue personnel at strategic points along its races. These professionals have a base of operations and sweepers who monitor the final participants.

Still, running in the heat is a problem no matter where you’re doing it or how much support you have, VanSciever said. He emphasized the importance of staying hydrated and going prepared for an event like the Boney Mountain Half Marathon.

Already, this summer has seen several heat-related deaths. Earlier in May, one hiker died and four others had to be rescued from Arizona’s Gold Canyon due to heat-related illnesses.

Cabral was a father of four. His family has started a GoFundMe campaign to help with funeral expenses.