Labour's mayoral candidate has accused the prime minister of racially profiling Londoners in a bitter row over campaign tactics.
Sadiq Khan claimed a letter sent by David Cameron to members of some ethnic communities was evidence of Tory desperation.
Labour Party member Barbara Patel was angered by a letter which appeared to think she was a member of London's Gujarati community.
Mrs Patel, a retired biochemist and translator from south London, is Jewish.
The letter included a headline: The Gujarati Community Makes London Great.
Khan, who is Muslim, said he was "disappointed" at the tone of the Conservative campaign.
A Conservative spokesman said the letter was a response to questions during visits by Zac Goldsmith to places of worship and community centres.