Spies plant cyber bombs in power grid

San Jose, Calif. —- Spies hacked into the U.S. electric grid and left computer programs that would let them disrupt service, exposing potentially catastrophic vulnerabilities in national infrastructure.

The intrusions were discovered after some electric companies let the government audit their systems, a former U.S. government official said.

The inspections were triggered by a March 2007 video of an Idaho National Laboratory demonstration of the damage hackers could do if they seized control of a crucial part of the electric grid.

The former official said the extent of the problem is unknown, because the government does not have blanket authority to examine other electric systems.

The sophistication necessary to pull off such intrusions is so high it was “almost without a doubt” done by state sponsors, the former official said.

The Wall Street Journal said officials believe the spies have not sought to damage the grid, but that they probably would try in a war or another crisis.