Although workplace shooting rampages are rarely carried out by women, a terrifying exception occurred a few weeks ago in California.

What is believed to have been the worst-ever incident of workplace violence committed by a woman took place at a postal outlet in Goleta (in Santa Barbara County).

Former postal worker Jennifer Sanmarco shot six workers with a 9 mm pistol before fatally shooting herself. Five workers and Sanmarco died at the scene and a sixth victim died later in hospital. Sanmarco was also believed responsible for the shooting death of a former neighbor in Goleta shortly before her shooting rampage at the mail sorting center.

She took medical leave from her job in 2003, after co-workers expressed concerns that she might harm herself. Sanmarco reportedly had been behaving oddly since that time, including having conversations with herself and being nude in public.