GRAHAM, Wash.  A man who fatally shot his five children and killed himself had just discovered his wife was leaving him for another man, authorities said Sunday.
The bodies of James Harrison's children, ages 7 to 16, were found with multiple gunshot wounds Saturday in the family's mobile home, most of them in their beds. Harrison's body had been found earlier in the day with a self-inflicted gunshot wound, behind the wheel of his idling car.
The night before, the father and his eldest daughter went in search of his wife, Angela Harrison. The daughter used a GPS feature in her mother's cell phone to find her with another man at a convenience store in nearby Auburn, said Ed Troyer, spokesman for the Pierce County Sheriff.
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The woman told her husband she was not coming home, and was leaving him for the man with her at the store. The father and the daughter left, distraught, Troyer said.
Sometime after the children went to sleep, he shot each of them multiple times. Four died in their beds. The fifth was found in the bathroom, surrounded by signs of violent struggle.
"He wanted the kids dead," Troyer said. "It wasn't like he shot a few rounds. He shot several rounds."
Investigators believe he then returned to the area near the convenience store looking for his wife. His body was found near the store, Troyer said.
"We think he was going to go back to kill the wife," Troyer said. "He probably didn't find her and realized the gravity of what he'd done and shot himself."
Several weapons were found in the home.
Authorities have not released the names of the family. Relatives identified the couple as Angela and James Harrison and the children as Maxine, Samantha, Heather, Jamie and James.
Ryan Peden, Maxine's classmate, had 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, Peden said.
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"Maxine texted me at 11 p.m. Friday. She said: "I'm tired of crying. I'm going to bed,"' he said. His text to her the next day went unanswered.
Candy Johnson, an aunt of the mother, described Harrison as a strict, controlling husband and father who didn't allow his wife to make decisions without asking him first.
"My niece has been so controlled from the time she was young," Johnson said, adding that Harrison had impregnated Angela when she was 13.
State child welfare officials put Harrison on a parenting plan in 2007 after a "minor assault" on one of the children, Troyer said, adding that the father agreed to the plan and the case was closed.
Ron Vorak, who lives across the street from the family's trailer at the Deer Run mobile home park, 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."
The home, about 15 southeast of Tacoma, became a makeshift memorial Sunday as neighbors left cards and bouquets of flowers. School officials said they were arranging to have grief counselors available when teachers and students returned Monday.
"We're going to try to get through this the best we can given the circumstances," said Jeff Davis, Orting School District superintendent. "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, was a 10th grader at Orting High School. Jamie was in the eighth grade and her sister Samantha in the sixth grade at Orting Middle School. The two youngest, Heather and James, were second-graders at Orting Primary School.
The father worked as a diesel mechanic, and the mother works at Wal-Mart, said another of Angela Harrison's aunts, Penny Flansburg. Troyer, however, said the father worked as a security guard at a casino.
One neighbor, Sheree Lund, who lives in the mobile home park, signed a community notebook left in front of the family's house. She wrote: "God Bless the five little ones. God bring peace to Mom."
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Map highlighting location of Graham, Washington. At least five children have been found dead in a home in Graham, Washington in Pierce County located in the United States. The bodies were found on Saturday after officials in neighboring King County found the body of their father who committed suicide by way of a self inflicted gunshot wound.

According to the Pierce County sheriff's office, the ages of the children, one boy and 4 girls, range from 7-years-old to 16-years-old and all were shot and killed. Police went to check on the children's health after King County sheriffs contacted Pierce County regarding the father's suicide, whose name has not been released.

Authorities believe the 35-year-old man killed all five children before he killed himself, but the motive is not yet known.