Robert Roland collapsed late Wednesday evening after he began experiencing respiratory difficulties.

The Anderson Valley Fire Department said the 63-year-old died at the Ukiah Valley Medical Center early Thursday morning.

The cause of death has not been yet determined, but officials believe that Roland’s death was likely due to heart-related problems.

Department volunteer Dawn Ballantine says the all-volunteer squad of 41 firefighters is currently battling a 550 acre blaze, one of hundreds started by recent lightning storms.

Governor Arnold Schwarzenegger released at statement saying he is “deeply saddened” by Roland’s death and that flags at the state capitol will fly at half-staff to honor his work.