According to TMZ and other sources close to the situation, a reenactment of a shooting in San Fernando Vally Park that Rap Artist Snoop Dogg was allegedly involved in sent park goers running for their lives.

Apparently the police never sent a memo out to the public warning them that blanks would be used during the movie scene. 

Snoop Dogg was tried for murder and eventually acquitted for the reenactment story that was being told.