CARNATION, Wash. — A man and a woman have been arrested in the deaths of six people, likely family members and including two young children, at a rural property east of Seattle, authorities said yesterday. The two, a 29-year-old woman and a man in his early 30s, were being held for investigation of homicide, King County sheriff’s Sergeant John Urquhart said.

He said it was unclear whether the two are related, but they were known to the victims. The pair came to the crime scene after investigators arrived there this morning, were questioned by investigators, then arrested around 4 p.m.

Sergeant Urquhart said investigators had not determined a motive in the slayings.

The victims included a boy about age 3, a girl about age 6, a man and woman in their 30s, and a man and woman in their 50s. Their names were not released, but they were “most likely three generations” of one family, Sergeant Urquhart said.

Autxopsies have not been performed on the bodies, but the cause of death was most likely gunshots, Sergeant Urquhart said. They were most likely killed late afternoon or early evening on Christmas Eve, he said.

Earlier, sheriff’s Detective Bob Conner said earlier that authorities were searching the area for other possible victims, but insisted there was no danger to anyone else living nearby.