The top Democrat on the Senate Intelligence Committee said Wednesday that he has seen reports which make him concerned that Russian interference targeted Hillary Clinton in key swing states.

“As a former tech guy, what really concerns me is at least some reports, and we have to get to the bottom of this, that there were upwards of 1,000 paid internet trolls working out of a facility in Russia, in effect taking over a series of computers, which are then called a ‘botnet,'” Virginia Sen. Mark Warner said at a press conference. These botnets place malware on computer servers and are able to redirect traffic.

The Senate Democrat went on to say that these botnets would “generate news down to specific areas,” and that he has received reports, which he needs to verify, that these areas targeted were the key swing states of Wisconsin, Michigan, and Pennsylvania. Trump won those states by a little over 100,000 votes.

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Warner said that these botnets distributed “fake news” in the lead up to the election such as “Clinton is sick or Clinton is taking money from some source.” The Virginia senator also claimed Kremlin-backed news outlets such as RT and Sputnik dominated Google results when one searched “election hacking.”

“I’m not here to relitigate the election,” Warner said. He added that he merely wanted to put the “American public on a higher level of alert” about “huge, huge threats for basic democracy.”