Labour leader Ed Miliband has condemned the antisemitic abuse targeted at his shadow cabinet colleague Luciana Berger.
Mr Miliband said the abuse was “utterly appalling” and urged social media companies to do more to tackle the problem.
The JC had earlier revealed the extent of the attacks – including death threats – aimed at Ms Berger in the past ten days.
A neo-Nazi website based in the US is behind the co-ordinated campaign.
Mr Miliband said: “The antisemitic abuse that Luciana Berger has experienced over recent days is utterly appalling and has absolutely no place in our country. We must have no tolerance for this vile and abusive behaviour wherever we find it.
“The last Labour government passed laws to stop incitement to racial hatred – it is right that those laws are enforced to the fullest possible extent by the police and crown prosecution service.
“I would also urge social media companies to do more to proactively take down such vile abuse where there is clear evidence of an orchestrated campaign of incitement.”
Ms Berger received around 400 abusive messages on Twitter last week. Many carried the hashtags and images created by the American site, which urged trolls to join "Operation: Filthy Jew Bitch".
Labour MP John Mann, chair of the All-Party Parliamentary Group Against Antisemitism, raised the abuse in the Commons on Wednesday. He has subsequently secured a debate to discuss the antisemitic messages sent to Ms Berger. It is due to take place on Tuesday.
