An attack on California electrical transformers in April is believed by some to be a practice round for a terrorist attack on the U.S. power grid.
The coordinated attack began outside of Silicon Valley where attackers cut telephone wires at 1 a.m. on April 16, according to the Wall Street Journal.
About half an hour later snipers shot at an electrical substation for about 19 minutes, destroying 17 transformers in the process. The attackers escaped before police arrived and remain at large.
It took 27 days to repair the substation and crews had to reroute power around the site using Silicon Valley power plants.
The attack was "the most significant incident of domestic terrorism involving the grid that has ever occurred" in the U.S., said Jon Wellinghoff, who was chairman of the Federal Energy Regulatory Commission at the time. […]
The 64-year-old Nevadan, who was appointed to FERC in 2006 by President George W. Bush and stepped down in November, said he gave closed-door, high-level briefings to federal agencies, Congress and the White House last year. As months have passed without arrests, he said, he has grown increasingly concerned that an even larger attack could be in the works. He said he was going public about the incident out of concern that national security is at risk and critical electric-grid sites aren't adequately protected.
The Federal Bureau of Investigation doesn't think a terrorist organization caused the Metcalf attack, said a spokesman for the FBI in San Francisco. Investigators are "continuing to sift through the evidence," he said…
"This wasn't an incident where Billy-Bob and Joe decided, after a few brewskis, to come in and shoot up a substation," Mark Johnson, retired vice president of transmission for PG&E, told the utility security conference, according to a video of his presentation. "This was an event that was well thought out, well planned and they targeted certain components." When reached, Mr. Johnson declined to comment further.