From 1983 to 1989, I was an employee of Electromagnetic Systems Laboratories (ESL), a defense contractor in Sunnyvale, California. In February of 1988, a mass killing occurred there, arising from a stalking episode.

http://en.wikipedia.org/wiki/Richard_Farley

I have very little to add to this that isn't in the article, I did not know the killer, or any of the victims. I never spoke to Ms Black, although I knew who she was by sight, my softball team often played hers in the company league. She was a beautiful and accomplished young engineer. She was severly injured, but survived the shooting. The shooter, Richard Farley, is currently on California's Death Row.

ESL was a big company in a sprawling complex, and the shooting occured in a building on the other side of it, so I knew nothing of what was going on until security men ordered me and my team to lock ourselves in a "tank" (an electronically locked room-sized steel Faraday cage designed to protect our computers from electronic eavesdropping). I never heard any of the multiple shots that were fired by the killer. After several hours, while police were negotiating with Farley, we were told to leave the complex. I remember, a SWAT team was stationed behind my car, and I had to call my wife to pick me up so I could get home.

Although I witnessed no direct evidence of the attack, and knew none of the participants personally, I was not unaffected by the incident. ESL was never quite the same after that, and I know I left about a year later, although for other reasons. Still, the atmosphere of the place changed. In spite of management's compassionate and sincere attempt at providing counseling and other services, the mood and enthusiasm and morale at ESL never recovered. It had been a great place to work, and until then, I really enjoyed my time there.

A TV movie about this incident, "I Can Make You Love Me", starring Brooke Shields and Richard Thomas was made. It is pretty accurate in its depiction of events.