Zack Polanski has appeared to criticise the hero policemen who brought down and disarmed the Golders Green terror suspect.
The Green Party leader shared a tweet that said the two officers were acting 'violently' towards the knifeman who stabbed Shloime Rand, 34, and Moshe Shine, 76.
The retweeted post suggested that police were heavy-handed when the assailant refused to drop the knife.
The suspect, a British national born in Somalia named Essa Suleiman, was Tasered and arrested while carrying the blade and a backpack that police had no idea if it carried explosives.
Metropolitan Police Commissioner Mark Rowley described the double attempted murder as a 'horrendous act of violence'. He also said the suspect had a 'history of serious violence and mental health issues'.
In a Tweet later reposted by the leader of the Greens, an online critic said: 'So essentially his officers were repeatedly and violently kicking a mentally ill man in the head when he was already incapacitated by Taser'.
It led to accusations that Mr Polanski was 'more concerned' about the suspected terrorist's wellbeing than those he is accused of stabbing in the street.
Tory MP Neil O'Brien said: 'As usual, the Greens' sympathies are with the terrorist rather than the brave police officers stopping him'.
Zack Polanski has retweeted a post suggesting hero policemen who disarmed the Golders Green terrorist were heavy handed
Bodycam footage of the horrifying incident in Golders Green shows the alleged terrorist walk towards officers while refusing to drop the knife
Mr Polanski, pictured speaking to activists and supporters during the Green Party Big Day Out, on April 25 has been criticised for the retweet
JK Rowling criticised the Greens Party's leadership for failing to mention Jewish in their statements
Labour's Jonathan Hinder tweeted: 'This is so telling. Polanski hates the brave police officers who stopped this. He's more concerned about the antisemitic terrorist with a knife in his hand! Isn't that right Zack Polanski?'
Home Office minister Mike Tapp said he was 'disgusted' and claimed that the 'Green Party has hit a new low'.
The suspect Essa Suleiman, 45, is a Somali-born British national with a long history of violence and mental health problems
Labour MP David Taylor added: 'Zack Polanski's sympathy for a marauding antisemitic terrorist rather than his victims shows why his Green Party is so dangerous.
'How can anyone watch that video from Golders Green and not feel proud of the way those brave police officers wrestled with the attacker who would not let go of his knife?'
The Daily Mail asked Mr Polanski to comment.
After the terror attack, he wrote on social media: 'Horrendous attack in Golders Green. Thinking of the victims, their families and everyone who will once again be shaken by this attack. Thank you to all of those involved with the emergency response'.
His deputy leader Mothin Ali said: 'Devastating news from Golders Green this morning. My prayers are with everyone affected. We are in debt to the emergency services, including Hatzola, for their immediate response'.
Their responses were criticised by author JK Rowling, because they failed to mention the word Jew or Jewish.
The Harry Potter creator said: 'Why do leaders of the Greens have such difficulty naming the particular demographic likely to be most "shaken" and "affected" by two men from their community having their throats cut on a London street?'
It came as Mothin Ali encouraged legal action against his own party after local election candidates were dismissed and suspended having been accused of anti-Semitism.
Mr Ali reportedly told a Greens for Palestine group that the individuals should seek out 'serious legal advice' and put the 'party on notice straight away'.
A number of Green candidates have been suspended or stepped down after alleged anti-Semitic comments they made in the past resurfaced.
Zack Polanski has said he had confidence in 99 per cent of his candidates - but admitted that vetting had been a ‘real challenge'.
Saiqa Ali was found to have allegedly posted an image of an armed man wearing a Hamas headband under the phrase 'resistance is freedom'
Sabine Mairey has been accused of posting anti-Semitic content online, including the above
Ms Ali is standing for the Green Party in Streatham, South London
But in recordings leaked to The Times, Mothin Ali said he was 'very worried' about his party’s approach.
'What we need to do is we need to get some serious legal advice. We need to make sure that we are putting the party on notice straight away, and we need to start with some class action. Because it won’t be the end. They’re coming after more and more people,' he said.
Two Green candidates were arrested on Thursday.
The Metropolitan Police detained the two women aged 54 and 57 in London under section 19 of the Public Order Act before taking them into custody for questioning.
One post alleged to have been shared on Facebook by one of the suspects read: 'Ramming a synagogue isn't anti-Semitism. It's revenge.'