The Republican chairman of a powerful congressional committee said Thursday that he will ask the FBI for a new criminal investigation into Hillary Clinton's classified email scandal, focusing on the possibility that she perjured herself in sworn testimony to Congress.

Utah Rep. Jason Chaffetz, the chairman of the House Oversight and Government Reform Committee, asked FBI Director James Comey whether he had cause to charge her for lying in a statement she made to Ohio Rep. Jim Jordan during a 2015 hearing on the 2012 Benghazi terror attack.

'There was nothing marked classified on my emails, either sent or received,' Clinton said at the time.

Comey said in a hearing Thursday that the FBI had not investigated whether that statement was true, despite finding three documents with classification markings among the messages on her private server.

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INDIGNANT: House Oversight Committee chairman Rep. Jason Chaffetz said Thursday that federal law enforcement has one standard for Hillary Clinton and another for others who hold security clearances

CAPITOL GRILL: Comey answered questions in a House Oversight and Government Reform Committee hearing on Thursday

IT AIN'T OVER: A new criminal probe would complicate Clinton's presidential run as she gears up to accept the Democratic Party's presidential nomination

'Not to my knowledge. I don't think there's been a [criminal] referral from Congress,' Comey said.

Asked if he needed one, Comey told Chaffetz: '[I] sure do.'

'You'll have one,' said Chaffetz. 'You'll have one in the next few hours.'

Under questioning from South Carolina Rep. Trey Gowdy, Comey agreed that 'there was classified information' on Clinton's homebrew server, and that Clinton's early denials in that regard were false.

'There was classified material emailed,' he said matter-of-factly.

Asked whether it was accurate that none of those materials were 'marked' classified when Clinton sent or received them, Comey said: 'That's not true.'

'There were a small number of portion markings on, I think, three of the documents,' he said.

Later in the hearing he was asked directly what offense lying under oath would be and what punishment it could lead to.

'Perjury,' he replied. 'Felony. I can't remember precisely... years in prison.'

Comey was making his first appearance before Congress since announcing the agency's recommendation to not prosecute Clinton over her private email setup.

'Hillary Clinton created this mess,' Chaffetz said, declaring that Clinton 'made a decision. ... to avoid and bypass the safety, the security and the protocol of the State Department.'

'There doesn't seem to be any consequence' for Clinton, he said. 'It wasn't just an innocent mistake. This went on for years.'

Maryland Rep. Elijah Cummings acknowledged that 'there is a gap' between the evidence against Clinton that Comey outlined this week and the conclusions he reached.

'Even if it takes until hell freezes over, I beg you to close the gap.'

PERJURY? Clinton said during an October 25, 2015 congressional hearing that 'there was nothing marked classified on my emails, either sent or received,' a statement that turned out not to be true

GET READY: Comey (left) and Chaffetz (right) will be key figures in any new investigation moving foward

HOT SEAT: FBI Director James Comey faced a grilling from Republican lawmakers on Thursday

Attorney General Loretta Lynch said Wednesday that she accepted the recommendations and findings of Comey and of her career prosecutors and would not file charges against Clinton.

Lynch is likely to face questions of her own next week at a separate oversight hearing of the House Judiciary Committee.

Clinton campaign spokesman Brian Fallon criticized the basis for Chaffetz's hearing on Thursday morning, saying in a statement that 'House Republicans are launching yet another taxpayer-funded sham of an inquiry to try to hurt Hillary Clinton politically.'

'For weeks Republicans have said they trusted FBI Director Comey to lead an independent review into Secretary Clinton's emails, but now they are second-guessing his judgment because his findings do not align with their conspiracy theories.'

After the hearing had finished Fallon was singing a different tune.

'Despite the partisan motivations of this hearing, we are glad it took place and that Director Comey had the opportunity to expand upon his remarks from earlier this week,' he said. 'Director Comey's testimony clearly knocked down a number of false Republican talking points and reconciled apparent contradictions between his previous remarks and Hillary Clinton's public statements.'

Fallon said Comey's testimony 'shut the door on any remaining conspiracy theories once and for all.'

'While Republicans may try to keep this issue alive, this hearing proved those efforts will only backfire.'

Comey's decision, and the way he delivered it, infuriated Republicans who felt that the FBI director in his unusually detailed and critical televised statement Tuesday had laid out a sufficient basis for prosecution.

'There seems to be a double standard,' the committee chairman, Utah Republican Rep. Jason Chaffetz said on NBC's 'Today Show.'

'If the average Joe had gone through that, they'd probably have handcuffs on him and probably be in jail.'

House Speaker Paul Ryan, a Wisconsin Republican, has said 'there are a lot more questions that need to be answered' and, in a letter to Director of National Intelligence James Clapper, requested that Clinton be barred from receiving classified briefings for the rest of the campaign – a move that 'certainly constitutes appropriate sanctions.'

THE QUESTION: Jim Jordan is the Ohio Republican congressman who asked Clinton last year whether there was 'marked classified' material on her private server

FEEDING FRENZY: Capitol Hill turned into a circus on Thursday as Comey arrived to testify

NO BRIEFINGS: House Speaker Paul Ryan of Wisconsin has asked the Director of National Intelligence to withhold classified national security briefings from Hillary Clinton as her campaign moves forward

'There is no legal requirement for you to provide Secretary Clinton with classified information, and it would send the wrong signal to all those charged with safeguarding our nation's secrets if you choose to provide her access to this information despite the FBI's findings,' Ryan wrote.

Republican presidential candidate Donald Trump complained that the system was 'rigged' and Clinton 'made so many false statements.

In a stinging assessment of her email practices as secretary of state, Comey rebuked Clinton and her aides for being 'extremely careless' in their handling of classified information and contradicted many of the defenses and explanations she's put forward for months.

But he also said there was no evidence anyone willfully or intentionally mishandled classified information and that 'no reasonable prosecutor' would pursue such a case.