Authorities say a former patient killed a doctor and then himself inside a chiropractic office in Washington state.

Pierce County sheriff's spokesman Ed Troyer says a man walked into the McKenna Chiropractic Center in Wednesday morning and shot the doctor in an apparent murder-suicide.

Troyer says it's not known yet what led up to the shooting in the town of McKenna, about 30 miles south of Tacoma. Several people were at the office at the time of the shooting, but no one else was hurt.

The News Tribune reports that the gunman, who used a shotgun, was a 35-year-old patient. Officials say the 46-year-old victim was a doctor.