Law enforcement officials survey the site in the Sierra National Forest… (Mark Crosse / Fresno Bee )
Three state biologists and a contract pilot were killed Tuesday when their helicopter crashed in rugged terrain in the Sierra National Forest in Madera County, authorities said.
The state Fish and Game biologists were surveying deer when the Bell 206 copter clipped a large electrical transmission line and plummeted to the ground, the Madera County Sheriff's Department said.
Debris scattered across a quarter-mile in an area called North Fork near Redinger Lake, authorities said. The crash sparked a small fire.
The incident, which occurred about noon, was witnessed by two U.S. Forest Service officers who were roughly 100 yards away, said Erica Stuart, spokeswoman for the Sheriff's Department.
In a statement, Gov. Arnold Schwarzenegger called the crash a "devastating tragedy."
"We send our thoughts and prayers to the families and friends of the victims," he said. "Our hearts are with them during this difficult time," Schwarzenegger wrote.
The Fish and Game Department identified the three biologists as Clu Cotter, 48, of Fresno; Kevin O'Connor, 40, of Bakersfield; and Tom Stolberg, 32, of Fresno.
The pilot was identified by the agency as Dennis "Mike" Donovan.
"We are deeply saddened by the loss of our esteemed colleagues," said John McCamman, director of the department.
The crash site is in remote terrain at about 3,000 feet, authorities said.
Fire crews were dispatched about 12:15 p.m. The rescuers had to drive and then hike to the scene, according to officials.
"Access was difficult," said a spokeswoman for the California Department of Forestry and Fire Protection.
Once at the site, it took rescuers about 90 minutes to find the first three victims, authorities said.
The fourth victim, the pilot, was found later in the afternoon, according to the Sheriff's Department.
Authorities said investigators from the Federal Aviation Administration and the National Transportation Safety Board were dispatched Tuesday afternoon to lead the probe into the cause of the crash.