UPDATE: Officials indicate mechanical problems are to blame for the crash.  At least 9 are dead and more than 50 injured.

A vintage World War II-era fighter, performing at an air show in Reno, NV, spiraled out of control, slamming into the grandstands and killing the pilot and some spectators.

FOX's Anita Vogel reports from the West Coast Newsroom:

FOX's Adam Housley is in Reno with more details:

Listen to sound from amateur video of the crash HERE:

Tanya Briening watched the crash happen:

Another eyewitness was Angel Rosado, a videographer with FOX TV affiliate KDVR:

Tune in to your local FOX News Radio station for the latest on this story.