According to FBI data that looked at active shooter incidents from 2000 to 2016, there were a total of nine instances where a woman was either the sole shooter or a secondary shooter.
The last time a lone female shooter opened fire at a work place was in 2014 at an office space in California.
Since 2000, the bureau has only tracked nine other active shooter situations where there was a woman that started shooting.
Some of the more recent incidents include the April 2018 Youtube Headquarters shooting where three people were injured and the shooter killed herself. Another is the shooting in San Bernadino where a husband and wife started shooting in an office space that killed 14 people.
Out of the 250 or so shootings the FBI deems 'active' since the year started, that's only 3.6% percent of shooters that are women.
The bureau identified 250 active shooter situations across the country, eight of them in the Baltimore or Washington, D.C. metro area.