What is the fine-grained topic of the following text: Rocker Marilyn Manson pointed a fake rifle at concertgoers during a November 5 performance in San Bernardino, California, nearly two years after two terrorists used real rifles to cut down 14 people in a gun free zone on December 2, 2015. Only return the topic.
Marilyn Manson's controversial act of pointing a fake rifle at concertgoers in San Bernardino.