Still more questions than answers about last year's sophisticated sniper attack on a massive electric substation near San Jose.

At least two gunman with automatic weapons in the dark of night took more than 100 precision shots at the facility sending energy crews scrambling to keep the power on in the south Bay last April.

Shane Harris with Foreign Policy Magazine broke the story.  He says the FBI has been very tight lipped about the investigation.

"Sounds like something out of a heist movie, but the signs tend to point to some people who had some really sophisticated training but we still don't have a motive and we still don't know who the suspects were," Harris said.

The marksmen disabled 17 transformers that night causing millions in damage.  Congress is now pushing federal agencies to boost security of the electric grid.