WATCH: Senators discuss first findings in Russia probe

Watch the senators’ announcement in the video player above.

WASHINGTON — The chairman of the Senate intelligence committee said Wednesday the panel is continuing to investigate possible collusion between Russia and associates of the Trump campaign, but has not reached a conclusion yet.

Sen. Richard Burr, a North Carolina Republican, gave an update 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. “The issue of collusion is still open,” he said.

Burr also said the panel won’t publicly release the contents of about 3,000 Facebook ads that were linked to Russia. Facebook turned the ads over to the committee earlier this month.

The ads focused on divisive social and political messages and were seen by an estimated 10 million people before and after the election, Facebook has said.

Warner said the Russian effort to sway the election also involved attempts to test the vulnerabilities of 21 states’ election systems.

Burr said no vote counts were altered.