Protesters who targeted the home of Conservative Jacob Rees-Mogg and shouted at this children have been condemned by Downing Street and MPs.
A video on the Facebook page of the Class War group shows a man telling one of the Tory MP’s children “your daddy is a horrible person”.
Police officers stood between the protesters and the MP during the incident outside his Westminster home.
Downing Street said the “intimidation” was “completely unacceptable”.
“No elected member or their family should be subjected to intimidation or abuse in that way,” said the prime minister’s spokesman.
The Archbishop of Canterbury Justin Welby said it was a “shameful and disgraceful” episode.
And, also writing on Twitter, Labour MP Yvette Cooper said the children of high-profile politicians should never be regarded as “fair game”.
Labour’s shadow Brexit minister Jenny Chapman said the protesters’ behaviour was “abhorrent”.
She told the BBC’s Politics Live she was “ashamed if those people think they have anything to do with the Labour movement” and condemned the protest “without any reservation”, adding that the people in the video should “never be anywhere near someone’s children”.
In the Class War video, a protester asked Mr Rees-Mogg how much he paid his family’s nanny, and when she too came out onto the street, demanded to know her salary and told her she had “Stockholm Syndrome”.
A subsequent Class War Facebook post said people were getting their “knickers in a twist” over the footage, saying the MP’s family had come outside after the protesters arrived.
The protest is believed to have been staged by veteran anarchist Ian Bone, who has taken part in similar stunts in the past.
Conservative MP Anna Soubry said it was “more evidence of how low our politics has sunk”.