Longtime Clinton ally James Carville said Monday that FBI Director James Comey’s bombshell letter to lawmakers last week was a concerted effort by the FBI and House Republicans to “hijack an election.”

Mr. Carville strongly criticized Mr. Comey’s letter Friday informing lawmakers that the FBI was reviewing new emails that were potentially “pertinent” to its investigation into Hillary Clinton’s use of a private email server as secretary of state.

“He was acting in concert and coordination with the House Republicans. End of story,” Mr. Carville said of Mr. Comey in an interview with MSNBC host Thomas Roberts.

“If there’s not something substantial, and I mean really substantial, then this is, in effect, an attempt to hijack an election,” Mr. Carville said. “It’s got to be called for what it is.”

Mr. Carville tried to link House Republicans to the WikiLeaks reveal of John Podesta’s emails, accusing the GOP of coordinating with the KGB in order to damage Mrs. Clinton’s campaign.

“We do know that our democracy is under assault by the KGB,” he said. “To me, that’s something we ought to be talking about. That’s a very pertinent, relevant issue in this campaign. And people have to decide: do we want our country for ourselves and the people in charge or are we going to elect the KGB and the House Republicans to decide this election.”

Mr. Carville got increasingly annoyed after Mr. Roberts asked him to focus on the FBI and not the WikiLeaks emails. Mr. Roberts pointed out that Democrats had just cheered Mr. Comey in July when he revealed he wasn’t going to have charges brought against Mrs. Clinton recommended to Attorney Gen. Loretta Lynch.

“Why are you defending this?” Mr. Carville shot back. “Why are you sitting here when our democracy is under assault with the FBI acting at the behest of [Republican Rep.] Jason Chaffetz and sitting here acting like it is something legit? It is not. It’s an effort to affect this election. So Democrats and people across the country have to know this.

“You are sitting here defending an assault on American democracy,” he continued. “This is an unprecedented event that was done at the behest of the House Republicans that was leaked to the press by the House Republicans. And as we know the KGB is all over this election. And this is what we’re talking about.

“This is unbelievable eight days before an election and it’s more unbelievable that people like you are defending this,” he added. “We’re not going to come together with the Republicans and KGB working together, I’ll tell you that.”