Story highlights "(T)hey have been trying to do this kind of disinformation as part of their toolkit," King said

Trump referred to investigations into Russia's meddling in the US election as "a witch hunt"

(CNN) Sen. Angus King said Friday that the Senate intelligence committee investigation has yielded incontrovertible proof that Russia meddled in the 2016 presidential election.

"There is no doubt whatsoever that the Russians were behind an effort to interfere with our elections," King said, speaking on CNN's "New Day" just a day after the committee's first public hearing on the matter.

"There's no doubt this is a Russian pattern for years," the Maine independent said. "(T)hey have been trying to do this kind of disinformation as part of their toolkit ... they're doing it right now in France and Germany."

King was responding to a tweet from President Donald Trump on Friday in which he referred to the ongoing investigations into Russia's efforts to influence the US election as a "a witch hunt (excuse for big election loss)" led by Democrats and the media.

Mike Flynn should ask for immunity in that this is a witch hunt (excuse for big election loss), by media & Dems, of historic proportion! — Donald J. Trump (@realDonaldTrump) March 31, 2017

In the tweet, Trump said his former national security adviser, Michael Flynn, should seek immunity in exchange for his testimony to federal and congressional investigators in their probe.

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