(Bloomberg) -- Computer code connected to Russiancyberattacks by U.S. intelligence agencies has been found in alaptop computer at a Vermont electric utility, a development thatemerged a day after the Obama administration hit Russia withsanctions for hacking during this year’s U.S. election.

The laptop wasn’t connected to the power grid at the time, theBurlingtonElectric Department said in a statement on Friday. It said itscanned its computer network and found the malware after theU.S. Department of HomelandSecurity sent out an alert about the code to owners andoperators of critical infrastructure.

“We took immediate action to isolate the laptop and alertedfederal officials of this finding,” utility spokesman MikeKanarick said in the statement. “Our team is working with federalofficials to trace this malware and prevent any other attempts toinfiltrate utility systems. We have briefed state officials andwill support the investigation fully.”

Such a breach has long been a concern for the U.S. becauseknocking out a power grid could cause widespread disruptions andhamper police, fire and medical responders. For that reason,computers at utilities are routinely checked for intrusions.

Vermont elected officials denounced the Russian hacking.

‘Manipulate the grid’

“This is beyond hackers having electronic joy rides — this isnow about trying to access utilities to potentially manipulate thegrid and shut it down in the middle of winter,” Senator PatrickLeahy said in a statement on Friday. “That is a direct threat toVermont and we do not take it lightly.”

Governor Peter Shumlin and Representative Peter Welch alsoissued statements.

There was no indication of compromise to customer information orto the security of its system, Burlington Electric GeneralManager Neale Lunderville said in a note on the municipally-ownedutility’s website. Burlington Electric serves about 16,000residential customers and more than 3,600 commercial customers inVermont’s largest city.

Skepticism from Trump

U.S. intelligence agencies have identified the code that theutility found as one used in what they call operation “GrizzlySteppe,” a far-reaching Russian operation to interfere withNovember’s presidential election. President Barack Obama’sadministration on Thursday slapped sanctions on Russia for theintrusion and ordered the expulsion of 35 Russian operatives.

While lawmakers of both parties have backed Obama’s actions,President-elect Donald Trump has expressed skepticism at theconclusion of intelligence agencies that Russia was behind thehacking and release of e-mails in an effort to damage his campaignopponent, Democrat Hillary Clinton.

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“I just want them to be sure because it’s a pretty seriouscharge,” Trump said Saturday night in Palm Beach at his Mar-a-Lagoresort’s New Year’s Eve party. “When you look at the weapons ofmass destruction — that was a disaster and they were wrong,and so I want them to be sure. I think it’s unfair if they don’tknow.”

Trump has pledged to improve relations with Russian PresidentVladimir Putin, whose government has denied it was behind thehacking. He praised Putin on Twitter Friday for not retaliatingagainst the U.S. sanctions, saying “I always knew he was verysmart!”

On Saturday night, the president-elect said: “Hopefully we’regoing to have great relationships with many countries — andthat includes Russia and it includes China.”

Not first time Russia linked to utility cyberattack

Homeland Security confirmed it shared technical information withowners of critical U.S. infrastructure to aid them in identifyingcode involved in Grizzly Steppe. The discovery of the code by aVermont utility was reported earlier by the Washington Post.

It’s not the first time Russia has been linked to to a cyberattack on a utility. Hackers broke into computers at a utilitycontrol center in western Ukraine in December 2014 and shut downsubstations throughout the region, leaving tens of thousands ofpeople without power. U.S. Senate Armed Services Committee ChairmanJohn McCain, a Republican from Arizona, has said Russia was behindthe breach.

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