A small airplane crashed in a San Diego County park on Saturday morning, according to Cal Fire.
The downed plane was reported at around 10:15 a.m. near Slaughterhouse Canyon Road in Lakeside, within the Sycamore Canyon Open Space Preserve.
A hiker in the area just west of State Route 67 first reported the downed aircraft, Cal Fire Capt. Mike Mohler said.
A separate Cal Fire official told NBC that all three people aboard the plane were confirmed dead at the scene.
By 11:20 a.m., Heartland Fire crews had hiked to the scene of the crash and made contact with the airplane. The National Transportation Safety Board (NTSB) and FAA are now investigating the crash.
The aircraft was an experimental Lancair IV-P plane, said Ian Gregor, public affairs manager for the FAA Pacific Region.
It crashed under unknown circumstances.
The pilot of the plane had departed from Montgomery Field in San Diego and was headed for Deer Valley Airport in Phoenix, Gregor said.
The crash victims' identities have not yet been released.