U.S. senators discuss 1st findings in Russia election probe

The chairman of the U.S. Senate intelligence committee said the panel is still investigating possible collusion between Russia and associates of the Trump campaign, but has not yet reached a conclusion.

Sen. Richard Burr, a North Carolina Republican, gave an update Wednesday on the committee's investigation into Russian interference in the 2016 presidential election. He was joined by the committee's top Democrat, Sen. Mark Warner of Virginia.

Burr said the committee has interviewed more than 100 witnesses as part of its investigation and that more work still needs to be done.

He said "the issue of collusion is still open."

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The panel has interviewed former Trump campaign chairman Paul Manafort and Trump's son-in-law and adviser, Jared Kushner.

Burr said last week that "there's no evidence of anything" so far connecting the Trump campaign and the Russian interference.

On Wednesday, as Burr outlined how the investigation had been conducted and what they'll do next, Burr noted the committee can say that vote totals in the U.S. election won by Donald Trump were not affected by Russian meddling.

The Republican senator noted there's still much to be done to try to understand what happened, saying committee members hadn't determined that Russia was seeking to boost Trump in the 2016 election.

"They were indiscriminate," Burr said, noting one of the biggest challenges of the investigation is "it seems the overall theme of the Russian involvement in the U.S. election was to create chaos at every level."

In that, he said, it looked like they had been "pretty darn successful."

The committee leaders also talked about efforts to hack state election systems. Federal authorities notified 21 states last month that they had been targeted by Russian government hackers during the 2016 presidential election, around a year after the efforts were first discovered.

Warner was once again critical of the Homeland Security Department for being slow to notify the states, saying he was disappointed by the lag.

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The Senate panel has also been focused on Russian efforts to push out social media messages on Twitter and Facebook, and is examining more than 3,000 Russia-linked ads that Facebook turned over to Congress this week.

Facebook has said the ads focused on divisive social and political messages, including LGBT issues, immigration and gun rights and were seen by an estimated 10 million people before and after the 2016 election.

The Senate probe is separate from an investigation covering similar ground that has been overseen by Robert Mueller following the firing of FBI Director James Comey.

Mueller, also a former FBI director, in his role as special counsel has the authority to recommend criminal charges if necessary.