Labour faces civil war over the soul of the party as moderates blamed Jeremy Corbyn and the hard-left Momentum group that backed him for its catastrophic defeat.
Former home secretary Alan Johnson led the offensive as he branded Momentum a “cult” which he wanted to see booted out of Labour.
His comments came after Mr Corbyn said he would quit as leader early next year after the party suffered its worst general election defeat since 1935.
Scottish leader Richard Leonard came under fire from one MSP who said the very future of the party is in jeopardy north of the Border after it allowed itself to be “undermined” by the UK leadership during the campaign.
Mr Johnson pointed the finger of blame for the defeat squarely in the direction of Mr Corbyn and his hard-left agenda.
“Corbyn was a disaster on the doorsteps,” he said as he debated with Momentum leader Jon Lansman on ITV.
“Everyone knew he couldn’t lead the working classes out of a paper bag.”
He branded Momentum a “party within a party” and warned it was still seeking to control Labour’s direction, including the new leader.
Mr Johnson said: “I want Momentum out of the party – I want them gone. Go back to your student politics. I feel angry about this that we persevered with Corbyn for this kind of experiment of Back to the Future.”
Veteran MP Dame Margaret Hodge said the result represented the rejection of the entire Corbyn project.
She said that, under his leadership, Labour had become the “nasty party”, with anti-Semitism allowed to flourish.
“People just didn’t trust the economics, the confetti of promises that was thrown at the public without any clear and honest way they were going to be paid for,” she told the BBC.
“People didn’t trust us with the national security of the nation. People didn’t trust Mr Corbyn.”
Phil Wilson, who lost Tony Blair’s former seat of Sedgefield to the Tories, said attempts by the leadership to put the result down to Brexit was “mendacious nonsense”.
“Jeremy Corbyn’s leadership was a bigger problem,” he said. “To say otherwise is delusional.”
After losing the former Labour stronghold of Stoke-on-Trent North, Ruth Smeeth said: “This is a disaster. Jeremy Corbyn should resign now before his own count is in.”
Former Cabinet minister Hilary Benn said voters simply did not have confidence in Mr Corbyn’s leadership.
“Any Labour canvasser will tell you we knocked on too many doors where people said, ‘I’ve voted Labour all my life, but I’m not going to vote Labour on this occasion’, and they didn’t have confidence in the leadership of the party,” he said.
In Scotland, Edinburgh Southern MSP Daniel Johnson warned the outcome was “much worse” than the picture UK-wide and said “clear mistakes” were made north of the Border.
“We allowed our position to be overruled and undermined by Jeremy Corbyn and John McDonnell,” he said.
“In doing so, not only did we undermine any distinctive leadership of the party in Scotland, the constitutional ambiguity surrounding Brexit was compounded. If lack of clarity on Brexit was toxic at a UK level, ambivalence on Scottish independence has proved lethal in Scotland.”
But Mr Leonard insisted constitutional issues had played a “major role” in the party’s defeat.
“We must do more to win back the trust of people on both sides of the Brexit and Scottish independence debates,” he said.
“In 2021, I am determined that our 14 years of opposition will come to an end in the Scottish Parliament. This is ambitious but we should not apologise for our ambition.”
Mr Corbyn, 70, came under pressure to stand down immediately.
Speaking about the timetable for him to leave, Mr Corbyn said: “The national executive will have to meet, of course, in the very near future and it is up to them. It will be in the early part of next year.”
He added: “I have pride in our manifesto that we put forward and all the policies we put forward, which actually had huge public support.
“But this election was taken over ultimately by Brexit and we as a party represent people who voted both Remain and Leave.
“My whole strategy was to reach out beyond the Brexit divide to try and bring people together, because ultimately the country has to come together.”