Four people have died after the helicopter they were riding in plummeted from the sky and crashed into a field.

The crash happened on Sunday, August 1, in a remote area of Northern California.

According to the Colusa County Sheriff’s Department, the Robinson R66 chopper crashed at 1:15pm about 65 mile northwest of Sacramento.

The Federal Aviation Administration has said it is investigating the cause of the tragedy.

Deputies and Sacramento River Fire officers are said to have found the four passengers still inside the helicopter after it crashed. They were all declared dead at the scene and have yet be formally named, according to KCRA.

All four people onboard confirmed dead after helicopter crashes

Walt Seaver, who owns the tomato farm where the helicopter crashed, said he didn’t see any smoke as the helicopter came down.

The cause of the crash is currently unknown, and the FAA and the National Transportation Safety Board will work together to find out exactly what happened in the lead up to the crash.