MARYLAND — (CNN) Sen. Ben Cardin, the ranking member on the Senate Committee on Foreign Relations, said in a radio interview Wednesday that he doesn’t know the reason behind the Russian hacking into the 2016 presidential election.

“What has been publicly released by our Intelligence Community is that the United States was attacked by cyber and that Russia, at the highest levels, signed off on that type of attack and their purpose was to interfere with our free elections,” the Maryland Democrat said on WBAL Newsradio 1090.

He continued, “That’s what we do know. We don’t know their motivations and that’s one of the reasons why I have called for an independent investigation, similar to what happened in 9/11. That type of independent commission investigation so we can understand what Russia has done, make sure we take steps to protect us against any further attacks and take the appropriate response.”

CNN previously reported that the US Intelligence Community is increasingly confident that interference by Russians into the presidential election was in an effort to help Donald Trump get elected. Last weekend, The New York Times reported the Central Intelligence Agency reached that conclusion because Russian hackers targeted Republican organizations as well Democrats but only published information on Democrats.

As CNN reported as well, the FBI hasn’t found evidence yet to conclusively say the hacking was done to help Trump.

Cardin noted there were different views on the motivations of Russians hackers.

“Well, again, there’s information that I had that I’m not permitted to talk about,” he said. “But, there are different views and we should find out their motivations. And, that’s one of the reasons why it’s important for us to have that independent investigation.”

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