At 12:10 p.m. local time, Riverside County officers responded to reports of an "air emergency" involving a small plane which crashed into the California Rehabilitation Center in Norco, California.
An early FAA statement revealed that while there were no injuries on the prison yard ground, the aircraft "sustained substantial damage" and charred the the immediate earth where it crashed. Responding firefighters contained a fire triggered by the accident.
Authorities have yet to release any details pertaining to the pilot's identity, but the aircraft was quickly identified as the last surviving Northrop N-9M. The 1942 bomber model with a 60-foot wingspan acted as a test aircraft for the US Air Force during the development of experimental heavy bombers XB-35 and YB-35.
Though four N-9Ms were constructed in the same timeframe, all but one of the models were scrapped as heavy bomber research progressed.
According to The Drive, the aircraft was purchased by the Planes of Flames Air Museum in 1982 and underwent a lengthy restoration process before becoming a somewhat regular presence at the annual Chino Airshow since 1993.