The Senate intelligence committee announced late Friday an investigation of Russian interference with the U.S. election. Many Democrats believe Russian hacking cost Hillary Clinton the presidency.

Separately, many Democrats also blame FBI Director James Comey -- for re-opening an investigation of Clinton’s emails -- just 10 days before the election. And on Friday, Congressional Democrats let loose on him.

Democrats stormed out of a briefing on Russian hacking -- furious with one of the briefers, Comey.

James Comey spoke before Congress on January 13, 2017. CBS News

“The FBI director has no credibility,” said Rep. Maxine Waters of California.

“My confidence in the FBI director’s ability to lead this agency has been shaken,” said Rep. Hank Johnson of Georgia.

“The FBI director has no credibility,” said Rep. Maxine Waters of California said Friday, Jan. 13, 2017. CBS News

The closed-door briefing for all House members was confidential. But multiple lawmakers tell CBS News that the former chair of the Democratic National Committee, Rep. Debbie Wasserman Schultz, asked Comey repeatedly why he never called her personally to inform her that the DNC’s servers may have been breached by the Russians.

Comey balked, eventually admitting “no, we didnt.”

“There was some heat. There was some heat,” said Rep. Johnson.

The FBI and President-elect Trump have suggested the DNC was lax and uncooperative.

“They did a very poor job,” Mr. Trump has said.

DNC officials tell CBS News that from September 2015 until April 2016, the only person the FBI spoke to at the DNC was an outside vendor who provided IT services.

Hackers began posting the stolen emails online in June. The unguarded exchanges cost Wasserman Schultz her chairmanship.

Clinton campaign chair John Podesta’s emails were posted three months later.

“I don’t see the president-elect as a legitimate president,” said Rep. John Lewis of Georgia to NBC. “I think the Russians participated in helping this man get elected and they helped destroy the candidacy of Hillary Clinton.”

U.S. Rep. John Lewis of Georgia. CBS News

He and at least at least seven other Democrats have announced they will boycott the inauguration.

One of them is Arizona’s Raul Grijalva.

”I will at home, in Arizona,” said Rep. Grijalva.

Democrats on Friday accused Comey of a double standard: Speaking publicly pre-election about the Clinton investigation even as he stayed mum about Russia’s attempts to help Mr. Trump. But they have been reluctant to call for him to step down, because some worry about who Mr. Trump will appoint if he leaves.