Police were seeking the whereabouts of the parents and young sister of two children whose bodies were found in a coastal inlet.

The body of 5-year-old Zachary Michael Longo was found floating last Wednesday near Alsea Bay. The body of his 3-year-old sister, Sadie Ann Longo, was found three days later by divers, the Lincoln County sheriff's department said.

The children were identified on Monday. The state medical examiner's office ruled that both died of homicide, but provided no further details.

An autopsy of the boy's body revealed no obvious signs of trauma, sheriff's officials said. An autopsy of the girl's body was conducted Sunday, but authorities didn't divulge any information.

Their parents, Christian Michael Longo, 27, and Mary Jane Longo, 35, and a 2-year-old sister, Madison, were missing. The family had recently moved to Newport, a coastal town north of Waldport, from Ypsilanti, Mich., Lt. Sgt. Curtis Landers said.

Police were searching for two vehicles believed to belong to the Longo family, one of which had the personalized Michigan license plate "KIDVAN.''

Residents planned a prayer service Monday to remember the children. A steady stream of cars stopped at a bridge close to where the children were found; many people left teddy bears, balloons, and cards. Residents also planned a candlelight memorial for Christmas night.

"Something like this that happens in a small town is personal to everyone," said Gary Bessette of nearby Tidewater. "The more I think about it, the more I want to cry."