A Look Back At 11 Deadly U.S. Mass Shootings Since 2012

An attack at a Southern California social services center Wednesday became the latest mass shooting in the United States.
Here’s a look at some of the deadliest U.S. shootings since 2012:
– Dec. 2, 2015: As many as three gunmen believed to be wearing military-style gear opened fire at a social services center in San Bernardino, California, killing at least 14 people and wounding more than a dozen, authorities said. No one has been arrested in the shooting, and a motive is unknown.
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