Four people have died in a private helicopter crash in a remote part of the northern US state of California, CBS13 reported, citing authorities.

The Colusa County Sheriff's Office said the helicopter crashed Sunday afternoon local time. An emergency officer found four bodies at the crash site, at the same time their death was stated, RIA Novosti reports.

The sheriff's office also noted that the Federal Aviation Administration (FAA) and the National Transportation Safety Board (NTSB) are investigating the incident. The aircraft regulator told Fox 40 that a Robinson R66 helicopter had crashed.