GRAHAM, Wash. -- A man murdered his five children in their Graham trailer home before taking his own life in Auburn, Pierce County Sheriff's Department spokesman Ed Troyer said.

Troyer said the children, ages 6 to 17, were shot to death by their father, who a family member identified as 34-year-old James Harrison.

Harrison was found dead in his car in Auburn at 8 a.m. Saturday by two area children, Sgt. Scott Near of Auburn police said.

The man's car was found still running on the side of the road in the 4200 block of Auburn Way South about a half-mile north of the Muckleshoot Casino. Near said the Native American man had a self-inflicted gunshot wound to the head.

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No suicide note was recovered, Near said.

Ron Vorak, who lives across the street from the family's trailer at the Deer Run mobile home park near Graham, said he called 911 at about 3:20 p.m. Saturday after one of the family's relatives couldn't get anyone to answer the door.

"He knocked on the door, and knocked on a couple of windows," Vorak said of the relative. "He walked around the side of the house, looked into the window. He could see somebody laying on the bed."

Pierce County sheriff's deputies then responded at the home located in the 20400 block of 135th Avenue Court East and found four children murdered in their beds and the fifth slain in the bathroom. The four girls and the youngest child, a 7-year-old boy, apparently had been shot to death.

Authorities have not released the names of the family, but the mother's aunt, Penny Flansburg, identified the couple as Angela and James Harrison and the children as Maxine, Samantha, Heather, Jamie and James. The father worked as a diesel mechanic, and the mother works at Wal-Mart, Flansburg said.

She was at a loss to explain the crime.

"They were pleasant together," Flansburg said. "We can't even figure out why."

Ryan Peden, a classmate of the eldest daughter, who was 16, said she told him Friday night that her parents had gotten into a fight and her mother had left. The father followed the mother and tried to get her to return, said Peden, 16.

Removing the dead took two vehicles from the medical examiner's office, and authorities were still puzzling over what might have driven Harrison to slaughter his family.

By Sunday morning, the yellow crime-scene tape and dozens of investigators who responded to the scene on Saturday were gone. The home's front yard was littered with the toys of a children who will never play again: unused bicycles, a swing set, a trampoline and a basketball hoop.

A few people drove slowly by the scene, a neatly kept mobile home in a quiet park nestled among towering evergreens.

"How do you make sense out of something like this?" asked Jeff Davis, superintendent of the 2,100-student Orting School District where all five children attended school.

He said school officials were making arrangements Sunday morning to have grief counselors available when teachers and students returned to school.

"We're going to try to get through this the best we can given the circumstances," Davis said Sunday. "In a small community like this, we know these kids. Teachers know the kids. All the kids know the kids."

Davis said the eldest, Maxine Harrison, was a tenth-grader at Orting High School. Jamie was in the eighth grade and her sister Samantha in the sixth grade at Orting Middle School; and the two youngest, Heather and James, were second-graders at Orting Primary School.

"How could something like this happen?" asked Mary Ripplinger, whose kids were playmates of the slain children. "Everyone's asking: Why did he do it? It's not right."

Carolyn and Raymond Bader, a former neighbor of the family, told The Seattle Times they often heard the father yelling at the children. The Baders said they called the sheriff's department and Child Protective Services several times with their concerns.

"We did all we could to help these kids," Raymond Bader said. "We tried to protect these kids. We did what we could."

One neighbor, Sherre Lund, who lives in the mobile home park, signed a community notebook left in from of the family's house. She wrote: "God Bless the five little ones. God bring peace to Mom."