SEDONA, AZ - A federal investigator is combing through the wreckage of a small plane that crashed, killing four people near Sedona.
Authorities aren't sure what caused the single-engine Cessna to crash in a remote canyon Sunday.
National Transportation Safety Board spokesman Keith Holloway said Tuesday that the investigator is collecting radar data, air traffic control communications and any witness accounts.
Meanwhile, a medical examiner is working to confirm the identities of the four victims.
The plane crash was one of two in northern Arizona that happened just hours apart.
Holloway says a crew is recovering the wreckage of another single-engine Cessna that crashed near the Arizona-Utah border. The plane landed on a ledge south of Interstate 15 and the Virgin River Gorge. Two teenage brothers from Clinton, Utah, were killed.