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Senate Homeland Security Chairman Ron Johnson says that "our critical infrastructure is vulnerable"

His comments came in an interview on CNN's "State of the Union" on Sunday

Washington CNN  — 

The Senate’s homeland security chairman says he is “highly concerned” that infrastructure like power plants in the United States and Europe is vulnerable to ISIS attacks.

Senate Homeland Security Committee Chairman Ron Johnson, R-Wisconsin, said in an interview with CNN’s Jake Tapper on “State of the Union” Sunday that he’s worried about reports that the terrorists who attacked Brussels had also staked out and planned a strike on a nuclear power plant.

“I’m highly concerned about that, but not only in Europe – look at the attack on the Metcalf power station in California. We have not solved that. That’s a very disconcerting chain of events here,” Johnson said, referring to the 2013 sniper attack on a California energy grid substation, which took out power to parts of Silicon Valley.

He continued: “So trust me, our critical infrastructure is vulnerable to cyber-attack, to potential terrorist attack, and we are not taking this threat seriously enough. So it’s very concerning.”

Johnson called for “more robust” surveillance and a stronger U.S. military role in the Middle East.

But, he admitted, “We all have the problem of what do you do with the not-guilty-yet in free and democratic societies where you have the presumption of innocence. It’s a very difficult problem.”

And he faulted President Barack Obama for his push to close the Guantanamo Bay, Cuba, saying it hurt U.S. efforts to interrogate terrorists.

Johnson said the way the United States can obtain useful intelligence is “capturing people, detaining them and interviewing them over a long period of time, finding discrepancies between themselves, between their own testimony and that of their fellow operatives.”