Russian hackers penetrated U.S. electricity grid through a utility in Vermont, officials say - The Washington Post

While the Russians did not actively use the code to disrupt operations, according to officials who spoke on the condition of anonymity to discuss a security matter, the discovery underscores the vulnerabilities of the nation’s electrical grid. And it raises fears in the U.S. government that Russian government hackers are actively trying to penetrate the grid to carry out potential attacks.
https://www.washingtonpost.com/world/national-security/russian-hackers-penetrated-us-electricity-grid-through-a-utility-in-vermont/2016/12/30/8fc90cc4-ceec-11e6-b8a2-8c2a61b0436f_story.html