Senior politicians have railed against Tories who used violent imagery in attacks on Theresa May as the Brexit battle turned increasingly bitter.
In anonymous briefings, the Prime Minister’s opponents have suggested she would be “knifed in the front” and should “bring her own noose” to a meeting with backbenchers.
Robert Halfon, chairman of the Commons Education Committee, said the comments made the Tories look “awful” in the eyes of the public.
The Tory MP told BBC Radio 4’s World At One it was “clearly unacceptable” and was “a shame on them, it’s a shame on the Conservative Party”.
“We cannot start aping the kind of extremist trolls on Twitter and if MPs want to go around doing that they shouldn’t be members of our party at all,” he said.
Health Select Committee chairwoman Sarah Wollaston questioned the use of the language less than two years after Labour MP Jo Cox was murdered.
She said: “Shame on the spineless cowards on my benches who hide behind anonymity to use such disturbing and violent language.”
East Renfrewshire’s Tory MP Paul Masterton hit out at the “snivelling cowards”, adding that his staff would report it to the police if he was subjected to threats of being knifed or assassinated.
The Prime Minister’s official spokesman said Mrs May expected those in public life to avoid “dehumanising” and “derogatory” language.
“Personal vitriol has no place in our politics,” the spokesman said.
Brexiteer Mark Francois said the language was “unacceptable” but that he would not tell Chief Whip Julian Smith how to do his job.
He hit out at a “bunker mentality” in Downing Street, telling BBC Radio 4’s Today: “The problem is that there is a lot of frustration on the backbenches at the moment, both among Leavers and Remainers, at the general state of play.
“When you try to convey that to Number 10, no-one is listening.”
Pro-Remain Tory Anna Soubry attacked him on Twitter afterwards, saying she was “appalled” that he had tried to excuse the “disgraceful and dangerous language” used.
Tory Andrew Bridgen said the language was “unhelpful” and warned his fellow Brexiteers that it risked increasing sympathy and support for the Prime Minister.
The North West Leicestershire MP told Good Morning Britain: “At the moment that (language) is unhelpful. It won’t persuade colleagues to back a change of leadership.
“It’s actually going to be counter-productive at this point.”
Labour’s Yvette Cooper, chairwoman of the Commons Home Affairs Committee, said Tory whips should unmask the MPs using “vile and dehumanising language”.
Ms Cooper told BBC Radio 4’s Today programme that they were normalising violence at a time when women MPs were facing increasing hostility and little more than two years after Ms Cox was brutally murdered in the street.
She said: “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.”