SAN JOSE, CA (KTVU/CNN) - A sniper attack on a California power station is raising fears about other possible incidents.
The attack was captured on surveillance video.
On the video a brief streak of light can be seen, perhaps a flashlight carried by an attacker.
Then come the sparks, they are bullets hitting the chain linked fence that surrounds the Pacific Gas and Electric, or PG&E substation in San Jose, a station that feeds power to Silicon Valley.
California Congressman Henry Waxman, a Democrat, says it shows our electrical grid isn't adequately protected from both cyber and now physical attacks.
"This was an unprecedented and sophisticated attack on an electric grid substation with military-style weapons," he said.
The April attack occurred just before 1 a.m.
The snipers first went into an underground vault and cut telephone cables.
A half hour later, they sprayed the substation with bullets, for nearly 20 minutes, knocking out 17 transformers, according to PG&E.
When police arrived, the shooters were gone. But they found more than a 100 shell casings from a high-powered assault rifle.
There were no fingerprints, and it seemed like a professional job.
To prevent a black out, energy workers re-routed power, but it took nearly a month to make the repairs.
It was a little known attack and it's not clear what the motives were. But now months later, some now are trying to bring it to the forefront, arguing that if similar shootings were carried throughout the nation at once, collectively, they could take out a large chunk of the electrical grid, leaving millions in the dark.
Jon Wellinghoff is the former chair of the federal Energy Regulatory Commission and he has some suggestions.
"This is more about the larger issue of physical security of these high voltage stations nationwide and the need to ensure that some defensive measures start to be put in place," he said.
He suggests measures such as opaque fences instead of open chained ones that you can see and shoot through, and more sophisticated surveillance cameras to help identify suspects.
The FBI says at this point they don't see the San Jose attack as terrorism, but it is still investigating. The power company says it's working to improve security.
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