(CNN) -- The nine Republicans on the House Intelligence Committee have signed a letter calling on House Intelligence Chairman Adam Schiff to resign as chairman, Rep. Mike Conaway, the Republican who led the panel's Russia investigation, said Thursday.
Conaway pointed to the release of the special counsel's summary on Sunday to accuse Schiff, a California Democrat, of having "abused your position to knowingly promote false information."
"Your actions both past and present are incompatible with your duty as chairman," Conaway said at the beginning of a public committee hearing on Russian money laundering, reading from the letter. "We have no faith in your ability to discharge duties."
The call from the Republicans on the committee for Schiff to step down escalate the Republican attacks on Schiff, who has come under fire for his claims of collusion after Attorney General Bill Barr's letter to Congress quoted special counsel Robert Mueller's report as saying it "did not establish that members of the Trump Campaign conspired or coordinated with the Russian government in its election interference activities."
President Donald Trump tweeted on Thursday morning that Schiff should resign from Congress.
Schiff has not backed down in the wake of the Mueller summary, saying his committee will continue its investigation and that Congress and the public still need to see the full Mueller report. He responded to the criticisms on Thursday by accusing Republicans that they "think it's OK" members of Trump's team were willing to accept dirt from Russians.
"I don't think it's OK. I think It's immoral, I think it's unethical, I think it's unpatriotic, and yes, I think it's corrupt, and evidence of collusion," Schiff said. "I do not think that conduct, criminal or not, is OK. And the day we do think that's OK, is the day we look back and say that is the day America lost its way."
Asked about Trump's tweet, Schiff told reporters: "It's nothing new from this President."
But the letter shows that Republican challenges to Schiff's leadership are escalating, which began soon after Barr's summary was released Sunday.
"We should not be used as a platform to spread false information and bizarre conspiracies," said Rep. Devin Nunes, the committee's top Republican who was chairman of the committee in the last Congress.
Rep. Mike Turner, an Ohio Republican, went a step further and compared Schiff to Sen. Joe McCarthy, the 1950s campaign to hunt communists.
"With McCarthyism, we had Russia chasing after Russian communists. Now we have Schiff chasing after Russian collusion and those who would collude," Turner said.
House Speaker Nancy Pelosi told reporters Thursday she's "so proud" of Schiff's work on the committee and accused Republican lawmakers of being afraid of the chairman.
"So what is the President afraid of?" Pelosi asked during her weekly news conference on Capitol Hill. "Is he afraid of the truth? That he would go after a member, a chairman of a committee, a respected chairman of a committee in the Congress. I think they're just scaredy-cats, they just don't know what to do, so they have to make an attack. They did the wrong thing."
This story has been updated with additional developments Thursday.
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