MCMINNVILLE, ORE. ? A father apparently shot his four children and wife to death in their bedrooms, then used the shotgun to kill himself, authorities said Friday.

The shootings are believed to have occurred nearly three weeks before sheriff’s deputies found the bodies Thursday night, said Yamhill County prosecutor Bradley Berry.

A child's bicycle lies on the ground just beyond police crime-scene tape in the back yard of a manufactured home in McMinnville, Ore., where six victims of an apparent murder-suicide were found Thursday night. Robert Bryant is believed to have murdered his family inside their rural home before turning the gun on himself, said Yamhill County Dist. Atty. Bradley Berry.

The motive was unknown, but evidence indicated Robert Bryant, 37, killed his family, Berry said.

The children ages 9 to 15 were last at school on Feb. 22, and investigators believe the shootings occurred the following day.

School authorities made several attempts to contact the family after teachers noticed the children’s absence, said Karen Richey, assistant superintendent for the McMinnville School District.

“We had people knocking on the door several times,” but no one answered, she said. School officials weren’t alarmed because it is common for students to be absent during the flu season, she said.

Two sheriff’s deputies were in the vicinity Thursday night on an unrelated call when neighbors approached them to express concern about the family. The deputies used a ladder to look into a window and spotted the bodies.

Authorities said the body of Janet Bryant, 37, was found on the floor of the couple’s bedroom. Clayton, 15, Ethan, 12, Ashley, 10, and Alyssa, 9, were all found in their beds; their father was dead in the living room.

“It was a horrible sight,” Berry said.

The Bryants moved last summer to Oregon from the Sacramento, Calif., area, where they had lived for nearly a decade, said Mark Messier, a family friend. Court records show that before they moved, Bryant, a self-employed landscaping contractor, had filed for bankruptcy.

Messier said the family’s move came as a surprise.

“Their uncles and aunts and grandparents all loved those kids, and they wanted to maintain contact, but Rob wouldn’t let them,” Messier said. “We don’t even know when they moved. They just up and went.”