Benton County Coroner John Hansens released Friday the results of his investigation into the shocking deaths of two Kennewick teenagers this summer.

In a case that rocked the Tri-Cities and left some area residents initially fearing there may have been a killer on the loose, Hansen's found the death of 12-year-old Ethan Austin, and his 16-year-old sister Kaitlin Austin to be a murder-suicide.

Hansen's report indicated Ethan died of a single gunshot wound to the head, while his sister died from multiple gunshot wounds to her head and torso.

No motive has yet been found as to why Ethan murdered his sister then turned the gun on himself, but Hansen's report says no one else was involved in the incident.

The children were found in their Kennewick home June 9. Additional information could possibly be released in the near future.