Updated

A small airplane slammed into a sheer cliff in the mile-high mountains east of Phoenix and exploded, killing the six people onboard, including the pilot and his three young children who were to spend the Thanksgiving weekend with him, authorities said.

The body of one child was recovered and dozens of sheriff's search and rescue personnel worked Thursday to recover the remains of the other victims, said Pinal County Sheriff Paul Babeu.

A search and rescue team was in the rugged Superstition Mountains searching for three missing teenagers Wednesday evening and saw the explosion as the twin-engine plane hit the cliff, Babeu said. The searchers found the teens, then went up the mountain to try to reach the crash site.

Ten deputies who spent the night on the mountain were relieved by 10 more early Thursday. They and dozens of volunteers began searching the crash site at first light. Video from news helicopters Thursday morning showed the wreckage strewn at the bottom of a blackened cliff.

The dead included pilot Shawn Perry, 39, his two sons and his daughter, Babeu said. Morgan Perry, 9, Logan Perry, 8, and Luke Perry, 6, lived with their mother in the community of Gold Canyon in Pinal County. Their father lived in Safford in southeastern Arizona and owned a small aviation business there.

He had flown to the Phoenix suburb of Mesa with another pilot who co-owned the company and a company mechanic to pick up the children for Thanksgiving. The plane was headed back to Safford when it crashed.

The other pilot was identified as Russell Hardy, 31, of Thatcher, Ariz., and the mechanic was Joseph Hardwick, 22, of Safford.

Babeu said he personally notified the mother late Wednesday. The woman, who is divorced from the children's father, is also a pilot.

"This is their entire family -- it's terrible," Babeu said. "Our hearts go out to the mom and the (families) of all the crash victims. We have has so many people that are working this day, and we just want to support them and embrace them and try to bring closure to this tragedy."

There was no indication the plane was in distress or that the pilot had radioed controllers about any problem, the sheriff said.

It was very dark at the time, and the plane missed clearing the peak by only several hundred feet. The aircraft slammed into an area of rugged peaks and outcroppings in the Superstition Mountains, 40 miles east of downtown Phoenix, at about 6:30 p.m. Wednesday, authorities said.

People called 911 reporting an explosion near a peak known as the Flat Iron, close to Lost Dutchman State Park, sheriff's spokeswoman Angelique Graham said.

Witnesses saw a fireball and an explosion.

"I looked up and saw this fireball and it rose up," Dave Dibble told KPHO-TV. "All of a sudden, boom."

Rescue crews flown in by helicopter to reach the crash site reported finding two debris fields on fire, suggesting that the plane broke apart on impact.

"The fuselage is stuck down into some of the crevices of this rough terrain," Babeu said late Wednesday. "This is not a flat area, this is jagged peaks, almost like a cliff-type rugged terrain."

Video after the crash showed several fires burning on the mountainside, where heavy brush is common. Flames could still be seen from the suburban communities of Mesa and Apache Junction hours later.

The region is filled with steep canyons, soaring rocky outcroppings and cactus. Treasure hunters who frequent the area have been looking for the legendary Lost Dutchman mine for more than a century.

Some witnesses told Phoenix-area television stations they heard a plane trying to rev its engines to climb higher before apparently hitting the mountains. The elevation is about 5,000 feet at the Superstition Mountains' highest point.

The plane was a Rockwell AC-690A and was registered to Ponderosa Aviation Inc. in Safford, which Babeu said was co-owned by Perry.

Kenitzer said the Federal Aviation Administration and the National Transportation Safety Board would be investigating the cause of the crash.