Sadiq Khan has hit back at a sinister Conservative party attack advert that claimed he had "seized" power in the capital and used footage taken in the US to illustrate crime in London.
An eerie voiceover claimed he was in charge of Ulez enforcers who are "terrorising communities".
Over a clip of people running out of Penn Station in New York, a voiceover says: “In the chaos people seek a desperate reprieve, egged on by the Labour mayor who wants to decriminalise the use of illegal drugs.”
Mr Khan criticised Susan Hall over the ad, saying his Tory rival in the mayoral race and her party were "doing down London".
He told BBC London: "It is staggering that we have a Conservative candidate who is aspiring to be the mayor of our great city just doing our city down.
"I think it is unpatriotic always slagging off the capital city.
"But I'm afraid it is another example of my fear materialising which is this election from the Conservative Party view where there is misinformation, where there is lies and in this case clearly videos which was not of our city.“
Ms Hall's team insisted that she did not sign off the video and it was part of a central party campaign.
It was deleted shortly after being published and the New York footage replaced.
Mr Khan added: "We have had the Conservative candidate liking tweets that she is now saying was a mistake. Now she is trying to walk away from this video. That's not just doing down London, it's telling an untruth."
Ms Hall has been criticised in the past for "liking" a tweet which described the capital as "Londonistan" and another of Enoch Powell, who was best known for his infamous “rivers of blood” speech.
She said she had "learned" from the fallout over her social media activity,
"I've apologised for those tweets on numerous occasions," she told the Standard.
"I've learned from them. I've learned from the criticism and we move forward. But they've never come up on the doorstep."
