The Jefferson County Sheriff’s Office said a 911 call around 7:40 p.m. Sunday reported the crash outside the city of Madras, and deputies found the site with the help of power company officials.

“Due to the extent of the crash there were no survivors,” the sheriff’s Facebook post said.

Authorities did not specify the number of passengers in the single-engine plane. The sheriff’s office says it won’t release the names of the victims until identities are confirmed and families are notified.

The National Transportation Safety Board said it has opened an investigation into the crash, which involved a Piper PA-32. It will oversee the probe along with the Federal Aviation Administration, the sheriff’s office said.

The NTSB said one of its investigators arrived at the site Monday afternoon to document the wreckage before it’s sent to a secure facility for further evaluation.

Local power company officials found the wreckage after looking into a power outage in the area, the federal agency said in an email.