Tory MPs critical of the prime minister have been denounced for their "disturbing and violent language" and urged to remember the murder of Labour's Jo Cox.
At the weekend, amid fresh concerns at Theresa May's Brexit negotiating strategy, unnamed Conservatives told Sunday newspapers the prime minister is entering "the killing zone" and "assassination is in the air".
One former minister said: "The moment is coming when the knife gets heated, stuck in her front and twisted. She'll be dead soon."
In addition, Mrs May was told by one anonymous Brexiteer to "bring her own noose" to a crunch meeting with MPs on Wednesday.
However, fellow Tory MPs have expressed outrage at the graphic descriptions used by their party colleagues.
Sarah Wollaston, the chair of the House of Commons health and social care committee, posted on Twitter: "Shame on the spineless cowards on my benches who hide behind anonymity to use such disturbing & violent language about their own colleague & PM @theresa_may.
"Totally unacceptable. Have they learned nothing following the assassination of Jo Cox?"
Simon Hoare, a parliamentary aide to Home Secretary Sajid Javid, added: "Some of the language used in today's media coverage regarding @theresa_may is totally unacceptable, undignified and a disgrace to politics and public service.
"They should be ashamed of themselves. A period of silence from them would be welcome."
Former minister Nick Boles claimed the MP who spoke of a "knife" being used on Mrs May was "a very small man, in every respect".
He added: "Everyone in parliament knows who it is. So do all the journalists in the lobby. My suggestion: stop reporting his appalling statements."
Rachel Maclean, a parliamentary aide to the Home Office, replied to Mr Boles revealing she does not know the identity of the unnamed MP but added: "If I did I would have no hesitation in calling them out, and asking the person to apologise and retract them.
"This language has no place whatsoever in public life, regardless of how strongly people feel about the issues."
Scottish Tory MP Paul Masterton said: "If I was told to 'bring my own noose' to my next surgery, that I'd be 'knived', or 'assassinated', my staff would report it to the police.
"I don't really see why comments made by snivelling cowards on the back benches towards the prime minister should be treated differently."
Brexiteer Mark Francois agreed the remarks were "unacceptable" but said he would not tell chief whip Julian Smith "how to do his job".
He added a "bunker" mentality had meant Number 10 is not listening to the concerns of Tory MPs.
The comments about the prime minister were also criticised by Labour MPs, with Barry Sheerman tweeting: "This disgusting violent imagery used by a Tory MP against Theresa May is utterly reprehensible he is known for this kind of outburst & should be disciplined immediately."
Yvette Cooper, chair of the House of Commons home affairs committee, told BBC Radio 4's Today programme: "This is vile and dehumanising language towards a woman MP, towards a prime minister who, no matter how much you might disagree with her, is someone who is doing a job in public life.
"Nobody should be subject to that kind of violent language, which I think is normalising violence in public debate at a time when we lost Jo Cox, we have had threats against Rosie Cooper, we have had other violent death threats against women MPs.
"It's about time we do know who that Conservative MP who is making these threats, because maybe if they use that language they will stop doing so if they are being called out publicly from using that kind of vile and irresponsible language again."
Scottish First Minister Nicola Sturgeon told Tory MPs to "get a grip" and claimed such language "debases politics".
"I don't intend to dignify those specific anonymous comments with a response," the prime minister's official spokesman told reporters on Monday.
"What I would say is that the Prime Minister has always been very clear that we must set a tone in public discourse which is neither dehumanising nor derogatory, personal vitriol has no place in our politics."
Mrs Cox, the former Labour MP for Batley and Spen, was fatally shot and stabbed by neo-Nazi terrorist Thomas Mair in the run up to the EU referendum in 2016.
Earlier this year, an activist linked to banned far-right group National Action pleaded guilty to preparing acts of terrorism by plotting to murder West Lancashire MP Ms Cooper.