WASHINGTON - US senators warned Thursday of Russia’s “unprecedented” threat to American and European democratic institutions Thursday as they opened their first public hearing into Moscow’s interference in the 2016 presidential election.

With the main House probe in political disarray, the Senate Intelligence Committee took the lead investigating how Russia allegedly sought to skew the election in favor of President Donald Trump.

The hearings opened with testimony by academic experts on Russia’s history of political meddling, and will include more than 20 witnesses as the committee delves into allegations of collusion with Moscow.

On the witness list are top figures from Trump’s election team suspected of communicating with Russian officials during the campaign.

“The American public, indeed, all democratic societies need to understand that malign actors are using old techniques with new platforms to undermine our democratic institutions,” said Republican committee chair Richard Burr.

“This is not innuendo or a false allegation. This is not fake news. This is what actually happened to us,” said Democratic Senator Mark Warner, the committee’s vice chairman.

Just before the hearing began, Russian President Vladimir Putin again dismissed the US intelligence charge that he masterminded the election disruption effort.

Such charges are “absurd” and “irresponsible,” Putin said in the northern city of Arkhangelsk at an international forum on the Arctic. But US senators warned that Europe is now experiencing the same type of computer hacking and disinformation campaign that the United States did.

“Some of our close allies in Europe are experiencing exactly the same kind of interference in their political processes. Germany has said its parliament has been hacked. French presidential candidates right now have been the subjects of Russian propaganda and disinformation,” he added.

Trump declares war on

Republican conservatives

President Donald Trump declared war on members of his own party on Thursday by threatening the political careers of conservative Republicans who helped torpedo healthcare legislation he backed, but was quickly told the lawmakers will not bow to “bullying.”

In a Twitter post, Trump took aim at the Freedom Caucus, a bloc of the most conservative Republicans in the US House of Representatives, indicating he would try to defeat them in next year’s congressional elections if they continued to defy him. “The Freedom Caucus will hurt the entire Republican agenda if they don’t get on the team, & fast. We must fight them, & Dems, in 2018!” Trump said on Twitter. Because Trump faces unified opposition by Democratic lawmakers, he cannot afford to lose many Republicans as he tries to get his legislative agenda through Congress, including healthcare, tax cuts and infrastructure spending. But keeping Freedom Caucus members happy without losing the votes of Republican moderates has proven tough.

Representative Justin Amash, a Freedom Caucus member from Michigan, shot back immediately at Trump in remarks outside the US Capitol.

“Most people don’t take well to being bullied,” Amash told reporters. Asked if Trump’s comments were constructive, Amash added: “It’s constructive in fifth grade. It may allow a child to get his way, but that’s not how our government works.”

Since launching his presidential bid in 2015, Trump has shown little reluctance to assail fellow Republican political adversaries as well as Democrats, often in scathing terms.

Trump, a real estate magnate who touted his skills as a dealmaker in his White House campaign, previously accused Freedom Caucus lawmakers of snatching “defeat from the jaws of victory” with their opposition to Republican healthcare legislation he supported to replace Democratic former President Barack Obama’s 2010 Affordable Care Act.

Trump went farther on Thursday. He equated members of his own party with the opposition Democrats, reflecting the extent to which he felt betrayed by the conservative lawmakers after the collapse of his first major legislative initiative.

Republican House Speaker Paul Ryan told reporters, “I understand the president’s frustration,” adding that he shared the frustration. Ryan said he was encouraging Republican lawmakers “to keep talking to one another.”

The mistrust between the White House and hardline conservatives in Congress has called into question the next big item on Trump’s agenda, sweeping tax cuts.

‘BIG THINGS COMING’

Ohio Representative Jim Jordan, a co-founder of the Freedom Caucus, offered a more measured response to Trump’s remarks and avoided direct criticism of the president. Jordan said Republicans need to figure out how to work together to confront looming battles including the federal budget, appropriations and raising the US debt ceiling.

“Look, I’m not here to assign blame to anyone,” Jordan told the “Fox & Friends” program. “I actually think we better get this right because there are a lot of big things coming.”

“We better get it right now, figure out how we’re going to work together to do what we told the American people we were going to do, and not just pass a bill that no one supports.”

Republicans presented a unified front against Obama but have struggled to come together and support specific legislative proposals since Trump took office in January.

Freedom Caucus members opposed the Trump-backed healthcare legislation in part because they said parts were too similar to the Obamacare law it was supposed to replace. The called age-based tax credits in the bill intended to help people buy medical insurance an unwise new federal entitlement.

Ryan said in an interview aired earlier on Thursday he feared the Republican Party is pushing the president toward the Democrats so Trump can make good on campaign promises on an overhaul of the healthcare system.

“I don’t want that to happen,” Ryan told the CBS program “This Morning” program, referring to Trump’s offer to work with Democrats.

Some conservatives outside the Freedom Caucus bristled at Trump’s remarks about the bloc.

“I think he’s still just negotiating,” said Representative Thomas Massie, a Kentucky conservative who is not in the Freedom Caucus but close to some of its members.

Asked if this was a productive strategy by Trump to get Freedom Caucus members on board, Massie said, “We’re on his side. We just feel like he’s been misled on Swampcare,” referring to the healthcare legislation championed by Ryan.

Amash depicted Trump as now beholden to the Washington establishment.

“It didn’t take long for the swamp to drain @realDonaldTrump,” Amash wrote on Twitter. “No shame, Mr. President. Almost everyone succumbs to the D.C. Establishment.”

On Tuesday, Trump expressed optimism about getting healthcare legislation through Congress despite the failure of the House bill last Friday, telling a gathering of senators “that’s such an easy one” and that he expected lawmakers to reach a deal “very quickly.” Trump did not offer specifics, and White House spokesman Sean Spicer on Wednesday said Trump’s comments came during a “light-hearted” moment.