TONOPAH, Ariz. -- Investigators have identified the victims in Wednesday's big rig crash at a rest stop near Tonopah.

The driver of the tractor-trailer truck, who was declared dead at the scene, was Edward French, 45, of Long Beach, Calif.

French lost control of his vehicle and crashed into a caretaker's house, a spokesman for the Arizona Department of Public Safety said.

Five people were in the backyard of the home at the time of the crash. Four of them were taken to Phoenix-area hospitals for treatment. They are:

• Carlos Gonzales, 53, of Safford. He was transported by ground ambulance to St. Joseph's Hospital, where he was treated and released for injuries suffered by falling debris.
• Sharon Gonzales, 42, of Safford. She was taken by ground ambulance to St. Joseph's Hospital, where she was admitted for serious but non-life-threatening injuries.
• Nicholas Gonzales, 12, of Safford. He was also taken by ground ambulance to St. Joseph's Hospital, where he was treated and released for injuries suffered by falling debris.
• Adolfo Sedillo, 70, of Avondale. He was flown to Good Samaritan hospital, where he was admitted for treatment of serious but non-life-threatening injuries.

The fifth person, Jamie Beltran, 36, of Phoenix, sought her own treatment at St. Joseph's hospital, where she was treated and released for minor injuries.

The big rig was traveling westbound on Interstate 10 at about 12:15 p.m. when the driver somehow lost control and crossed over the eastbound lanes, said DPS spokesman Bart Graves.

"Fortunately, one of the subjects could see the trailer coming and told everybody in the backyard to run," said DPS Officer Roger Hansen.

Investigators said it doesn't appear as though the driver fell asleep at the wheel, but he may have had a medical episode like a heart attack or stroke. The medical examiner will make the final determination.

Authorities closed the rest stop to allow medical helicopters to fly in and out of the area, Graves said.

The crash did not prompt any I-10 closures. The truck didn't hit any other vehicles as it crossed the lanes, Graves said.

Reporter Greg Gurule contributed to this story.