An Oregon teen is accused of shooting and killing his foster mother and his two sisters in Portland.

KRON 4 reports that the 16-year-old boy, Kevin Adams, is in police custody after surrendering at the scene of the killing on Tuesday night.

The victims, Donya Adams, 55; her biological daughter Amory Adams, 26; and 10-year-old foster daughter Payshience “Tia” Adams were found shot to death inside the home. Tia is believed to be the suspect’s biological sister.

Police had responded to the residence when Kevin’s foster father called to report that his family members had been killed. According to court records obtained by the New York Post, the father, Robert Adams, told detectives that he returned at about 6:30 p.m. Tuesday to find his family had been slaughtered and a gun left on his bed.

Douglas County Sheriff’s Lt. Chris Merrifield reportedly wrote in the police affidavit that the suspect confessed to shooting his family members. A motive for the triple murder is not yet known.

This is a developing story. CrimeOnline will provide an update when more information is available.

[Feature image: Douglas County Juvenile Detention Center]